Design Insights from Sustainability Apps to Guide User Centered Mobile Application Development

Design Insights from Sustainability Apps to Guide User Centered Mobile Application Development | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Design Insights from Sustainability Apps to Guide User Centered Mobile Application Development Eva Cipi, Eljona zanaj This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7310678/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This paper explores the role of mobile applications in promoting sustainable behaviors and environmental awareness. The researchers study the related issues of the impact of sustainability-oriented app design on user engagement and motivation. Using a mixed-methods exploratory approach, the researcher analyzed 54 mobile applications from the Google Play Store, categorized by interaction type (informative, gamified, or both), environmental theme (e.g., ethical consumption, carbon tracking), and user review availability. Of these, 21 apps with user feedback were further analyzed using Natural Language Processing techniques. The VADER sentiment analysis was used to determine user satisfaction and the topic modelling analyzed using the LDA topic modelling to identify common themes. The findings highlight that app success relies not just on informative content or basic gamification, but on clear, motivational content that links sustainability goals to practical daily actions. Users value straightforward interfaces, consistent performance, and ethical accessibility. More importantly, the research defines three frequently neglected yet fundamental aspects of mainstream app design: inclusivity, affordability, and transparency. The thesis underlines that these aspects have a serious influence on the trust of the user community and a long-term involvement. The study provides a user-based recommendation on design solutions that developers can use to develop ethical, user and context-sensitive sustainability applications. In general, the thesis can be useful in the domain of digital sustainability, creating bridges between the principles of design and user expectations to improve the role of mobile technology in achieving sustainable behaviors. Mobile Applications Sustainability User Interaction Strategy LDA Modeling Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 I. INTRODUCTION Mobile apps have evolved into highly complex systems that not only change human behavior in an individualistic manner but also collectively. They have influenced the personal sustainability participation by using educational materials that monitor the behavior, and they also offer motivation to green actions. The digital solutions are now applicable to the climate change and environmental degradation struggle in two ways: promoting sustainable practices, developing communal participation, and maintaining the citizen science program. Mobile applications can also be the part of the solution of environmental concerns with the help of conservation, waste and sunshine use activities [1, 2]. They have developed a combination of educational materials with interactivity and promotional strategies to make such an approach an innovative environment that allows coming together of technological novelty and the protection of the environment. The job of the mobile applics as the facilitators of sustainable behavior is monitored in several correlated ways. The rapid technological development coupled with changes in user needs, however, creates obstacles to the evaluation of the long-term consequences that cannot be neglected. Assessing an app based only on the isolated mechanism of accessing pure user review can potentially subject the entire exercise to potential misleading outcomes and incompleteness. Consumer rating is typically done on convenient answers or mainstream branding as opposed to a long-term impact. User feedback contains valuable information yet needs systematic evaluation to extract significant patterns while preventing broad interpretations. Contrary to digital health, there is no standard model in which to analyze user data in sustainability app assessment [3]. This gap points to the need for more nuanced and multidimensional methods that can account for the complex relationship between app features, user experience, and environmental impact. Based on the current trends, digital sustainability is depicted as capitalizing on advanced analytics and machine learning to provide customized recommendations and immediate feedback. In addition, these applications transform into community empowerment platforms that enable collaborative governance and connect individual actions to broader policy objectives. One example that could be given is The Internet of Things (IoT)—once merged with mobile technology, it allows for detailed environmental metric tracking that leads to improved transparency and accountability [4]. The development and implementation of these technologies are now heavily focused on ethical aspects, such as data privacy, user consent, or transparency without them due to the greater social awareness of social consequences [5]. II. LITERATURE REVIEW Research studies have investigated different aspects of mobile applications for sustainability by studying their design elements and engagement mechanisms, as well as their ability to create enduring positive behavioral shifts. Although gamification is associated with motivation, such approaches have not been used uniformly in sustainability applications on phones [6]. Other than being entertaining alone, it should also encourage pro-environment behavior. The broad variety of the design strategies and user motivation methods results in applications serving as sources of information or systems that employ persuasive mechanisms through challenges, rewards and tracking progress as behavioral regulators. Although such variations can provide valuable data regarding the advocacy of digital sustainability, the difficulty in evaluating and comparing apps on a set of standardized criteria persists. This lack of formal guidance has led to an uncomfortable standstill in the process of moving forward to adopt a green mindset in which we are to act consciously or we will never thrive with the environment. Developers need to get over their green rhetoric and start writing apps that really promote sustainable behavior. The guide is intended as a stepping stone to more thoughtful app designers and can be regarded as a means to an inspiration as opposed to a list of what is best. It prompts some questions such as: What is the type of behaviour we are encouraging? Do our gamification methods have any significance or are they just garnish? Or are we helping in the autonomy of the users, or are we pushing them too hard?. A. The Concept of Sustainability in Mobile Apps Recent research findings challenge the traditional theory on the nature of mobile apps as inanimate tools and prove their capability of dynamic modification of human behavior. One paper pointed out that apps do not serve existing human objectives but rather ally themselves with other systems, leading to unanticipated interactions and having the potential to transform habits fundamentally [7]. This new perspective holds fundamental importance in sustainability considering mobile apps for sustainable mobility, waste management, and green food practices can reconfigure how people handle resources and protect the environment [8, 7; 9]. There has been conducted extensive research also on persuasive technology which functions as a mechanism to promote desired behavioral modifications. The Persuasive Systems Design (PSD) model presents a detailed framework that explains how mobile apps can influence users toward sustainable behavior adoption [8]. Waste management applications utilize reduction and personalization alongside tailoring and self-monitoring persuasive strategies to reduce user effort in target behaviors while providing ongoing feedback [9]. The research demonstrates users will interact extensively with systems that deliver appropriate guidance to reach behavioral targets and deliver individualized information that supports knowledge absorption through clear explanations. The research on energy efficiency, the inclusion of sustainability as a quality parameter for Information Technology and Systems, as well as as other variations uncovering the connection between software engineering and green practices have been predominantly more extensive than the more granular work needed specifically for applications [10; 11; 12;13;14;15;16; 17; 18; 19; 20]. The latter has been seemingly sporadic over the last decade and has gained more traction only the recent years. Service-oriented software development typically starts with unlimited resource assumptions but real-world data centers use energy that exceeds what tens of thousands of households would consume [21]. Research has demonstrated how mobile applications support sustainability efforts across waste management, green food practices, and sustainable travel behavior [22; 23; 24]. Different applications have unique priorities since they provide either advanced monitoring capabilities or they embed sustainability features into popular mainstream applications to provide users with better convenience and encourage eco-friendly behavior [24; 25]. B. Gamification as a Catalyst for Sustainable Behavior The Gamification as a preferred design strategy for digital advocacy applications seems extremely promising as a way to foster user engagement while influencing behavioral patterns. Developers embed game elements such as badges and leader--boards into routine applications to create an entertaining experience for users that helps boost user retention as well as extend app longevity [26]. The application of gamification techniques in sustainability efforts targets the promotion of recycling, energy conservation, and responsible consumer behavior. A research study by [27] showed that gamified challenges led users to experience both higher enjoyment and knowledge acquisition, which resulted in real behavioral transformations. Different gamification features generate different impacts on behavioral shifts. Another study found support for the conclusion that some gamified interventions sometimes fail to reduce resource consumption but other approaches show potential in speeding up environmentally responsible actions. This study establishes how gamification requires sophisticated understanding to achieve lasting behavioral shifts and demonstrates the need to identify effective game design features [28]. Gamification should not aim to make sustainability more palatable by simply reshaping existing consumption patterns. Rather, it should support a deeper transformation in how users relate to sustainability—as a lifestyle, not just a feature [29]. C. Current Evaluation Criteria for Mobile Apps For assessing sustainability applications we need to use diverse evaluation methods. Research studies have evaluated digital tools through usability metrics and user engagement indicators along with behavior change models. The research on gamification and persuasive technology delivers essential knowledge about digital interventions that affect user motivation. Users remain doubtful about sustainability claims unless digital tools demonstrate transparent methodologies and obtain third-party certifications [30]. Mobile sustainability applications require a specialized evaluation framework that has not been developed yet, differnetly from health and education mobile apps which, as we have already mentioned, have been subject to more extensive research. Health evaluation frameworks have experienced substantial growth because they offer standardized methods to evaluate usability, privacy, clinical effectiveness, and overall app quality [31]. Mobile applications are evaluated using multidimensional rating systems, including MARS and its derivatives which combine content validity with user experience and data privacy assessment [32]. Sustainable mobile applications need an established evaluation framework because they face similar challenges from rapid innovation and frequent updates alongside balancing technical performance against behavioral impact. Researchers demand a complete assessment framework that unites multiple domains such as content validity, user experience, engagement, interoperability, technical features, and privacy into one unified structure [32]. The literature emphasizes that user-centric design and culturally specific development approaches are essential for sustainability app creation. Users currently favor sustainability features which are integrated into widely used apps instead. The research evidence demonstrates the importance of involving end users in co-design activities for developing apps because it ensures these applications match their daily habits along with their personal tastes and cultural backgrounds [33]. Users are largely excluded from the development phase of both software and applications. As final remarks, the research shows an entanglement of initial efforts into exploring specifically gamification technology, persuasive design methods, and mobile platforms for reaching sustainability targets. The field has achieved substantial progress, but this does not indicate that major gaps in knowledge do not continue to persist. The greatest part of current research about gamified apps neglects to study the complete range of sustainability applications. III. EXPLORING DESIGN PRINCIPLES FOR SUSTAINABLE MOBILE APPLICATIONS Mobile applications that immerse into sustainability challenges need their design to match usability and engagement targets while fulfilling environmental and ethical requirements. The following section combines sustainable and green UX/UI design best practices with mobile app design and user-centered ethics guidelines based on industry reports, design agencies, and expert blog publications. A. Minimizing Environmental Impact through User Experience As a first step, sustainable design requires an application to have a reduced digital and environmental footprint. This is achievable by optimizing User Experience (UX), to decrease energy consumption and processing power usage. An example of what can be categorized as UX optimization is using weight reduction techniques for the minimization of high-resolution multimedia elements like images, videos, and complex animations, enabling applications to achieve both faster loading speeds and decreased data usage. Subsequently, CO emissions associated with data transfer and processing are reduced considerably [34]. There is another article that supports the idea of using compressed multimedia assets and also provides additional ways to converge to mindful app design, including efficient coding practices and app bloat reduction. Users are enabled in this way to finish tasks through fewer clicks and navigation steps, reducing their screen time and energy usage. These methods ensure an improvement in ecological efficiency while also enhancing user satisfaction [35].. B. Balancing Engagement and Sustainability Sustainable app design is expected to create a balance between engagement strategies and ethical as well as environmental concerns. The implementation of gamification and habit loops for user retention improvement requires careful consideration. An exclusive focus on engagement can marginalize sustainable practices, leading to increased device usage, push notification fatigue, and superficial reward systems that further promote consumerism. This is, in fact, supported by the literature, as discussed in the respective section, which highlights how certain efforts can backfire—hindering genuine change by reinforcing the very sources of the problem [36]. Designers should implement mindful interactions that help users achieve their goals without creating distractions or excessive resource consumption. Users gain control over their experience through customizable notification preferences, energy-saving features, and data collection transparency that enables them to make conscious choices regarding their preferences [37]. C. Behavior Change Design Techniques Beyond Gamification The popularity of gamification for user engagement in sustainability apps should not overshadow the fact that behavior change design uses multiple strategies which extend past game mechanics. Sustainable mobile applications can use the five key themes of the Behavior Change Strategy Cards developed by Artefact Group to implement various techniques that enable ethical and holistic influence on user behaviors [38]. ● "Make It Personal: The Persuasive Power of ’Me’ and ’My’". The process of personalization makes sustainability goals and actions more relevant and motivating through individualized framing. The approach includes tailoring feedback to match user-specific contexts and habits, encouraging self-monitoring and reflection, as well as goal creation that aligns with one’s own personal beliefs. ● "Tip the Scales: How Perceptions of Losses and Gains Influence Our Choices". This category leverages insights from behavioral economics by framing choices to highlight perceived gains or losses. The way this works is that apps can use two different approaches to encourage the adoption of sustainable behavior: either by showing users the advantages of sustainable actions (health benefits and cost reductions), or the negative outcomes of inaction (environmental harm and resource waste). ● "Craft the Journey: Why the Entire Experience Matters". It is understood in this present context that behavior change does not occur via disjointed individual interactions. It, instead, requires an effective user journey. This process requires the simplification of difficult tasks and the ability to provide a clear representation of progress made, and it also incorporates educational materials that can illustrate the impacts of behavior in the environment. ● "Set Up the Options: Set Up the Options to the Desired Decision. Choice architecture is a process that serves as an instrument that guides the users towards sustainable decisions. Designers are supposed to make green choices the default choice and decrease choice overload by limiting arbitrary decisions and adding mental reminders or triggers at decision points. ● "Keep It Simple: Avoiding Unwanted Result. The problem with behavior change is that individuals are more likely to get stuck when they have faced situations that are complex or daunting. When the interfaces are simplified and barriers as well as interruptions are either minimized or averted, users keep on being motivated and consistent. D. Green IT and Sustainable Development Practices Shifting the lens beyond the interface, backend operational practices are also responsible for affecting the environment. The implementation of green IT strategies that support digital sustainability includes practices such as selecting a host server that is powered by renewable energy, reducing server load, and using efficient databases and APIs [39]. Additionally, mobile developers are encouraged to monitor the environmental impact of their products throughout time, by using tracking tools to measure energy consumption and digital carbon emissions. E. Ethics and Inclusivity Despite it being intuitive, it is important to be explicit in stating that green design does, indeed, stand in both social and ethical dimensions. The “Society-Centered Design” movement and “Climate Designers” network state that ethical technology must protect user rights while making products accessible to them and building community empowerment [40]. F. Green Design Trends in Practice Practical applications of green technology serve as additional evidence that demonstrates how the mentioned principles become actualized. The user interfaces of “Energy Saver”, “EcoBuddy” and “Gaia” demonstrate minimalism through restrained colors while maintaining efficient features that prevent digital and cognitive strain [41]. These apps witness how sustainable design is achieved by preserving both user satisfaction and aesthetic appeal, thus without the need to compromise either element with the purpose of affecting the environment as little as possible. The combination of dark mode functionality with local caching and carbon awareness indicators in the interfaces enables users to track and manage their digital carbon footprint. Such features combine practical functionality with educational elements that lead users toward sustainable practices by implementing sustainability principles throughout their usage journey. IV. METHODOLOGY This research is driven by adopting an exploratory approach to analyze existing mobile applications that promote sustainable behaviors. A systematic selection and categorization of the relevant apps from the Google Play Store is the first building block of this methodological process, aiming to form a curated dataset of mobile tools aimed at supporting green practices. Rather than conducting a mere traditional content analysis, this phase integrates both qualitative and computational techniques for enriching the understanding about the effectiveness of the collected apps, user perceptions, and engagement dynamics. This analysis sets the foundation for developing informed recommendations that may guide app designers in enhancing digital advocacy for environmental sustainability. A. Platform Selection and Search Terms Google Play Store was chosen because of its accessibility, open publishing, and extended developer reach. Android devices rule the global smart phone market, especially in regions that favor affordable open-source platforms. It has a quick review and open nature, which attracts many developers, including those in the emerging markets, to publish sustainability-related applications. The lower barrier to entry on the Play Store often results in a wider array of app types, including niche or experimental green initiatives that may not pass the stricter quality control of the Apple ecosystem. The open nature of this platform works well with research exploration because it enables an extensive evaluation of digital environmental advocacy tools. For the sake of broad and relevant coverage, two primary search terms were used: ● “Green” ● “Sustainab-” This choice reflects a strategic departure from another research study, which used only one term due to constraints in their search strategy, considering the two interchangeable [42]. B. Application Selection Criteria The process of selection of applications for the research was designed to be fair and retain significance using an approach that balanced reach, relevance and reliability. The final analysis is based on apps that meet several pre-defined inclusion criteria. Establishing these requirements guaranteed total transparency and maintained integrity throughout the entire selection process. The first practical criterion evaluated the availability of language support. Only English and Italian apps were chosen to make correct qualitative analysis of the researcher. The selection of apps with English or Italian language support allowed both interface and content interpretation, and also enabled a more nuanced qualitative evaluation of its tone, messaging, and functionality. Beyond language, the applications also needed to demonstrate relevance and engagement in one of the three key ways to qualify for study participation. Indicating a certain download volume will be helpful to notice whether an app has achieved notable public visibility and user engagement, establishing its relevance in the sustainability app market. To make sure the apps selected for this study had a meaningful level of public engagement, a threshold of 10,000 downloads was used. The selection choice followed the research approach of another body of work which established this benchmark to evaluate health apps because it demonstrated their visibility and meaningful user interaction . Regarding external recognition, the inclusion of apps depended on their validation through partnerships with credible organizations, certifications, or endorsements from subject matter experts, which added credibility to their selection. The inclusion logic for app selection can be formalized as follows, This reasoning was motivated by assessment criteria applied in the evaluations of digital health apps proposed by Henson et al (2019): Include App →↑ Language ↓ {English, Italian} ↔ (Downloads > 10,000 ↗ Strong Sustainability Focus ↗ Expert Approval) An override condition was applied in cases where apps had no downloads. Specifically: If Downloads = 0 ↔ Strong Sustainability Focus ↑ Manual Inspection In other words, apps with zero downloads but demonstrating a strong sustainability focus were manually evaluated to determine their relevance and potential inclusion. C. Observations and Exclusions During the app selection process multiple specific patterns emerged, which determined the final composition of the dataset. These findings proved important for the methodology while also revealing significant problems that exist in sustainability apps regarding branding deception, limited scope and concerns about long-term relevance. Many applications emerged to fulfill particular narrow use cases which dominated the market. Two examples of complementary applications can be "Green Drive" which assists car users and "Sustainable Ocean Alliance" which concentrates on ocean environmental initiatives. The search results showed that keyword selection played a major role during the investigation. The search term “green” yielded many applicable apps yet most of these results also appeared when using the more effective “sustainab-” keyword, which, as we already discussed, encompasses “sustainable” and “sustainability”. The search term “green” yielded only five relevant results that also appeared in the “sustainab-” search results. The selection of the “sustainab- ” keyword became the final criterion to build the list of 54 apps. Using only the “sustainab-” keyword for the selection process improved efficiency while demonstrating the value of selecting appropriate search terms for systematic reviews. D. Keyword Electiveness and Relevance The entire search process through app stores heavily depended on metadata and keyword matching which made success dependent on the quality of selected terms that matched sustainability-related digital tools. Three different keywords received initial testing to investigate sustainable apps which included "green," "sustainab-" and "environment." Among these three keywords the keyword "sustainab-" delivered the most relevant results because of its high number of quality search outcomes. Using the root term "sustainab-" which encompasses terms such as "sustainable" and "sustainability" brought forth the most significant number of apps that might match study criteria. Shifting the focus to the results obtained from the search conducted based on the keyword "green", it can be observed that there is an inconsistency in comparison to the other two key words. E. Categorization by User Interaciton Strategy This application categorization is defined based on the main user interaction method employed, which relies predominantly either on game-like mechanisms or the delivery of informative content working as different motivational approaches to encourage user participation. Thus, one of the focal points of the classification process was separating applications according to their strategy of interaction, i.e., whether they employ gamification or adhere to a more informative mode. Also, engagement will be used interchangeably with interaction in this section. Gamified apps are designed to be engaging and fun, borrowing from video games in an effort to encourage regular use. Such features can be as straightforward as awarding points, unlocking badges, completing levels or missions, maintaining streaks, or climbing leaderboards. Others include avatars or interactive stories. Actually, some apps incorporate aspects of both types. In such instances, a decision was made regarding the predominant mode of interaction. F. Categorization by Review Availability The second main criterion on which the shortlisted applications were classified was whether they have received any user reviews from real users on the Google Play Store. To go beyond basic observations into deeper insights regarding the preferences and dislikes of users related to how apps fit into their sustainable lifestyles, the applications were sorted into two main categories: ● Apps with reviews: Representative of apps having either ratings, written feedback, or both. This is an extremely helpful subset of the dataset since they reflect first-hand user experience ● Apps without reviews: Representative of apps that had not yet been downloaded by users or had the review feature disabled for some unknown reason. By separating apps into those with and without reviews, this categorization ensures that the evaluation remains grounded in real-world usage wherever possible. G. Categorization by Thematic Focus The final dimension of categorization involved the thematic content of each app, referring to the type of sustainability issue it sought to address. The categories can be observed through Table 1. To deepen this thematic analysis by connecting it with global priorities, and also create more familiarity with the themes, the app categories were mapped to the United Nations Sustainable Development Goals (SDGs) [43]. Mapping the apps to relevant SDGs allowed for a clearer understanding of how digital solutions align with broader sustainability frameworks. Thus, these categories illustrate the various types of digital solutions that can be used to promote sustainable conduct. The apps are flexible in their reach regarding target audience. All users–be them beginners in building sustainable habits or deeply committed to an eco-friendly lifestyle–can benefit from these apps which serve as valuable resources offering information, motivation, and opportunities to connect with the ones who share the common goal of creating a more sustainable world. H. Sentiment Analysis of User Reviews The evaluation of mobile applications focused on sustainability requires knowledge about how users experience and use these digital tools. This research uses sentiment analysis as a widely recognized Natural Language Processing (NLP) technique to extract meaningful patterns from review data. The fundamental purpose of sentiment analysis is to enable researchers to automatically assess whether user-generated content gravitate toward a positive, neutral, or negative sentiment. The analysis focused on sustainability applications with Google Play Store user reviews from the selected 54 applications. The information structure includes the category, a short description and relevant SDGs as it is is presented at the Table 1. The sentiment analysis was conducted by making use of the VADER (Valence Aware Dictionary and sEntiment Reasoner) tool which operates as part of the Natural Language Toolkit (NLTK) in Python. To retrieve the review data, the Google Play Scraper Python library was employed. While the function was configured to retrieve up to 500 of the most recent reviews per app, the actual number of available reviews varied significantly across the sample. The number of reviews on some apps reached only five or six while other apps had received between 400 and 500 reviews. This difference in number of reviews stems from natural variations between apps regarding their popularity, user interaction, and the time available in the market. The text of each review was then processed by VADER, which produced a compound sentiment score ranging from -1 (extremely negative) to +1 (extremely positive). These scores were averaged per app to obtain an overall sentiment value, which was then categorized into positive, neutral, or negative based on standardized thresholds: scores above 0.05 were labeled as positive, those below -0.05 as negative, and values in between were considered neutral. To reiterate, despite the sample size limitation, this sentiment analysis represents a valuable first step in understanding how sustainability apps are perceived by their users in practice. I. Topic Modeling of User Reviews Sentiment analysis gives useful information about user attitudes through emotional polarity measurement, however, it fails to identify the actual content of user discussions. For this reason the present study uses topic modeling as a second natural language processing (NLP) technique to analyze the specific themes, expectations, and concerns that users express in the reviews left for sustainability-focused mobile Table 1 applications. Through topic modeling researchers can move past basic emotional assessments of user comments to detect hidden patterns in how people communicate about digital tools. J. Data Collection and Review Preparation The topic modeling analysis was conducted on the same dataset of user reviews used in the sentiment analysis phase. This included 21 sustainability apps (from the original set of 54) which had available English-language reviews on the Google Play Store. As with the sentiment analysis, the Python library "google_play_scraper" was used to collect up to 500 of the most recent reviews for each app. To ensure reliable linguistic consistency for the modeling process, once again only reviews in English were retained. The Python library "langdetect" was also used in this case to detect non-English entries that were then removed from the analysis. The topic modeling algorithm requires English-language data because as, similarly to VADER, it has been tested and optimized for content in English, and may struggle to interpret non-English text with sufficient semantic accuracy. The final dataset consisted of a consolidated corpus of English reviews distributed across the 21 selected apps, offering a balanced perspective from both widely used and more niche sustainability apps. The analysis became more robust by combining all filtered English-language reviews into one dataset. The collective modeling technique maintains user perspectives from various sustainability domains while revealing common themes and concerns which exist across different app in this landscape. K. Preprocessing for Topic Modeling Extensive cleaning and preprocessing had to be applied to the text corpus before the application of the topic modeling algorithm to enhance model clarity and performance. Each review was initially converted to lowercase, then it followed that the punctuation marks, numeric characters, and non-alphabetic symbols had to be removed. The Natural Language Toolkit (NLTK) was used to eliminate Standard English stopwords which include words like “and,” “the,” “is” since they do not contribute much semantic value. The Porter Stemmer was applied to each word to transform them into their base or root form (e.g., “distracted,” “distracting,” and “distract” all become “distract”). The process unified related concepts while decreasing the number of dimensions which proves essential when working with short and informal texts such as app reviews. The cleaned text had to finally go through its final layer of preprocessing, which is tokenization, to generate individual words before being organised in a manner that is compatible with topic modeling standards. The Gensim Dictionary class generated a dictionary of terms while doc2bow converted each review into the format of Bag of Words (BoW), used to determine how frequently were terms recurring in documents. L. LDA Modeling Implementation The research applied Latent Dirichlet Allocation (LDA) because this established unsupervised machine learning method effectively extracts topics from text data and demonstrates reliability for NLP tasks with short-form user-generated content. The Gensim Python library served to implement the model. The final number of topics used in the research are five, after testing different topic counts between four and ten. The five-topic model achieved an optimal balance between thematic understanding and distinct topic separation. Probabilistic convergence of the model was guaranteed by ten passes. An important feature of LDA modeling is the lambda () parameter, which influences how words are ranked and interpreted within each topic. When = 1, the term ranking is based on overall frequency across all topics—highlighting the most common words. A λ = 0.4 gave much emphasis to topic-related terms and words and downplayed the generic ones, making thematic issues clear. The interpretation of topics through both values creates a dual perspective which reveals the general emotional or functional context ( = 1) and the specific conceptual nature of each topic ( = 0.4). To visualize topics and detect overlaps, pyLDAvis was utilised. This enabled an exploration of how the topics relate to one another spatially, the most salient terms for each topic, and the relative frequency and relevance of those terms. The interface allows a deeper inspection of each topic’s structure and is especially useful for identifying overlaps or potential ambiguities in topic boundaries. M. Integrating Topic Modeling in the Broader Analysis The implementation of topic modeling together with sentiment analysis serves to create a fuller and more useful understanding of user experience. As sentiment scores measure emotional satisfaction, topic modeling reveals specific aspects to which users are reacting. Together, these tools provide a rich, complementary foundation for evaluating sustainability apps—not only in terms of how they make users feel, but also in relation to what users value, criticize, or recommend. The research approach, however, has certain boundaries that need to be recognized. The analytical value of topic modeling is arguably relevant, but several factors need to be taken into account. First, the number of reviews used, although filtered for quality and language consistency, remains modest due to the fact that not all sustainability apps receive substantial public feedback. Thus, the findings may not be generalizable, but they still provide useful qualitative insights into the recurring themes among users who are using these apps. Second, stemming and stopword removal—while improving model efficiency—may sometimes lead to the loss of contextual nuance, particularly in short user reviews. Yet, these steps were necessary to enhance model performance considering the unstructured and frequently disorganized nature of app store language. Finally, the topics discovered are best interpreted as thematic cues rather than definitive categories. Their value lies in their ability to highlight user priorities and recurring issues that might otherwise be overlooked when evaluating app effectiveness solely based on numerical ratings or isolated comments. The Table 2 shows the four topics according to the sustainability categorization. V. RESULTS A. App Categorization In this part initially presents the categorization outcomes and user review availability across the selected sustainability apps. The collection of 54 apps is displayed in Table 2 and it represents a wide range of thematic categories, offering valuable insights into how digital tools interpret and promote sustainability. Table 3 illustrates the distribution breakdown in terms of all dimensions of categorization. A dominance of mixed interaction models is observed: more than half of the apps (55.56%) utilize both gamified and informative elements. The dataset consists of 31 percent informative, and 13 percent gamified-only apps. In terms of thematic focus, the most populated category is Carbon Footprint Tracking and Climate Action (24.07%). Then Environmental Awareness and Education follows (20.37%). Sustainable Consumption and Product Transparency (18.52%), which has strong links to SDG 12 (Responsible Consumption and Production), and Sustainable Lifestyle and Habit Building (14.81%), typically using gamified nudges to impact daily choices, are also themes that stand out. The presence of the Sustainable Mobility and Green Finance applications (each ~3.7%), indicates the new dimension of interest in SDG 11 and SDG 9. Additionally, having access to user reviews is useful to further enrich the analysis on app performance. A starking 61.11% of the collected apps do not have visible user reviews on the Google Play Store. The apps with reviews were used for the sentiment analysis and topic modeling presented in subsequent sections. Technology is being increasingly leveraged to conduct sustainabilityrelated efforts that aim to reflect progress in the areas targeted by the SDGs. This conclsuion is grasped through the intuitive yet layered analysis conducted so far. B. Sentiment Analysis Overview A summary table (4) was generated to show the number of reviews extracted for each app and the reviews that made it to the final analysis contribution stage after language filtering. This data is included to provide transparency about the amount of reviews that was used to calculate each sentiment score and to help to understand the results better. Each app is plotted in Figure 1 by average sentiment score (X-axis), theme category (Y-axis) and interaction type (bubble color and size) (based on compound VADER analysis) and grouping them vertically by thematic category. The analysis includes English language reviews which determine both the bubble size and color based on whether the app uses informative or gamified content, or both. C. Topic Modeling Overview The LDA algorithm was used to analyze English-language user reviews through topic modeling for extracting deeper insights about user perceptions and priorities. The five generated topics consist of thematic clusters that show common user concerns, preferences, and sentiments about the sustainability apps studied. ● Topic 1: Engagement, Enjoyment, and Brand Enthusiasm This topic dominates the model with 31.6% of total token representation. It is positioned as the largest bubble in the upper-left quadrant of the pyLDAvis visualization and it also overlaps partially with Topic 3. What this means is that, these two topics share some shared thematic areas related to user appreciation and app enjoyment. Fig. 2 ● Topic 2: Technical Frustrations and Usability Concerns The second topic contains 22.8% of tokens and appears as a medium-sized bubble in the lower left quadrant. The bubble remains near the main cluster (Topics 1 and 3) but presents a different story which apparently focuses on challenges and frustrations that users have experienced. Fig. 3 ● Topic 3: Environmental Impact and Climate-Oriented Behavior Change. From topic 3, it can be seen that 21.9% of the total tokens are pertaining to it, and as already highlighted above, it overlaps with Topic 1, indicating shared themes. The bubble is located in the left part of the visualization and slightly above and to the left of Topic 1. The thematic connection between emotional satisfaction and sustainability driven motivation becomes evident through this overlapping area. Fig 4 ● Topic 4: Food and Product Transparency. As for the fourth topic, it makes up 15% of the total corpus while located in the bottom left quadrant where it stands apart from the core cluster of Topics 1–3. The spatial distance indicates a clear conceptual boundary as this topic focuses mostly on food-related matters. Fig. 5 ● Topic 5: Ethical Search, Pricing, and Eco-Friendly Shopping. In the pyLDAvis map Topic 5 is shown as the smallest and most distanced topic, with only 8.7% representation out of the total tokens, being positioned in the top-right quadrant away from all other topics. What can be apprehended from the isolated position of this topic is that it represents a distinct thematic domain that is not strongly linked to the other user experiences seen so far. Fig. 6 The topic modeling application on the reviews from the collected apps in this study provides a thematic map of what users value, praise, or critique in sustainability apps. The most dominant areas—Topic 1, Topic 2, and Topic 3—suggest that users are drawn to apps that are enjoyable, well-designed, and purpose-driven. These are the most prevalent areas to be addressed, however it is important to take into consideration also more niche priorities emerging among some of the discussions, such as health transparency (Topic 4) and cost-conscious browsing (Topic 5). VI. Discussion The results are interpreted in this section with the help of previous studies in the field of persuasive design and digital sustainability. This section uses the literature review to reflect on the implications of the categorization patterns and sentiment analysis and topic modeling results for app designers and researchers who want to use mobile technology to promote environmental behavior. The study makes use of empirical data, building upon existing findings to propose practical insights which will help create more effective and ethically sound sustainability apps. The discussion begins by revisiting several important patterns from the app distribution analysis, especially the design approaches and interaction strategies that establish the foundation for a deeper examination of user experience, values, and motivation. A. Insights from App Categorization As indicated in Table 1, the gamification phenomenon is common particularly in apps aiming to transform daily behavior, like the carbon tracking apps or lifestyle apps, with many apps incorporating challenges, point systems, streaks, and reward mechanisms—design elements previously discussed. When it comes to categories like Sustainable Lifestyle and Habit Building, and Carbon Footprint Tracking and Climate Action, they are the ones that stand out for their gamified engagement strategies. Trying to interpret this result, it may easily make sense as to why this occurs, considering these apps very explicitly aim to encourage daily behavioral changes, directly aligning with goals such as SDG 12 (Responsible Consumption and Production) and SDG 13 (Climate Action). As supported by the literature, gamification can provide a quicker convergence of habits omitting extensive explanations and triggering direct action [44] It is to say that the effectiveness of these apps heavily depends on individual motivation and external circumstances, and hence, despite their well-defined intended purpose to promote sustainable habits through interactive motivation systems, their performance can vary substantially [45] Moving forward, apps that focus on Sustainable Consumption and Product Transparency, or Green Finance and Business Sustainability, generally use an informative approach instead. Two examples can be Good On You and Code Check, which function primarily as databases and scanners instead of interactive platforms. These applications provide extensive product details, ethical assessments, and financial recommendations which serve to educate users instead of providing entertainment. These apps are also in line with SDGs 8 and 12, which help to promote ethical consumption. This distinction emphasizes the importance of aligning an app’s interaction strategy with its intended outcome: while gamification is a useful tool for behavior change, information-driven apps are also, quite intuitively, expected to benefit more from clarity, credibility, and trust [46]. The selected sustainability apps represent the extensive pool of digital developments in advocating for sustainability, yet numerous apps which are newer or niche, lack user reviews on the Google Play Store. The relatively high number of apps without user reviews (61.11%) may at first seem like a limitation, but the limited visibility does not necessarily reflect their quality or potential. Therefore, these apps that are slowly expanding the market for digital sustainability promotion, each in their own unique way, have taken up the role of digital ambassadors of the SDGs, contributing to a variety of the goals they comprise, from raising awareness for quality education (SDG 4), to encouraging climate action (SDG 13), or supporting sustainable cities and communities (SDG 11) [47]. B. Insights from Topic Modeling The analysis of user reviews through topic modeling reveals detailed insights about how users understand and use mobile applications focused on sustainability. Sentiment analysis serves to capture the general emotional direction of the user feedback, whereas topic modeling serves to unfold the particular discussion topics including concerns, characteristics, and expectations that users have mentioned in their feedback. The five identified topics reveal distinct user experience perspectives. The following interpretations analyze these themes to reveal design strategies which work and those which do not in this domain. ● Interpretation of Topic 1: Engagement, Enjoyment, and Brand Enthusiasm. Topic 1 indicates that respondents prefer emotionally appealing, effectively designed applications (gamified or informative in nature). The design perspective of this topic demonstrates how emotional engagement and ease of use should be a careful consideration of designers as they need to create user experiences that are not only functional, but also rewarding and enjoyable. ● Interpretation of Topic 2: Technical Frustrations and Usability Concerns . Topic 2 indicates that one cannot simply have ethical intent without technical reliability. Developers should note that trust can erode quickly when technical issues go unresolved or when expectations set in the app description are not delivered in practice. ● Interpretation of Topic 3: Environmental Impact and Climate-Oriented Behavior Change. Consumers prefer applications that cause actions to be directly tied to climate impact [48]. ● Interpretation of Topic 4: Food and Product Transparency. Food and product apps must provide correct product information and fast responses [49]. ● Interpretation of Topic 5: Ethical Search, Pricing, and Eco-Friendly Shopping. The 5th topic indicates the need in cost-conscious functionality that sustains ethical consumption behavior. The five topics together provide an extensive view of the repeated themes and user preferences within the sustainability app ecosystem. Users seek emotional engagement alongside ethical clarity, technical reliability, and real-world usefulness in their sustainability apps. C. Design Guidelines Informed by User Feedback and App Patterns The research findings present an analytical summary of mobile applications related to sustainability, but the purpose of this study extends beyond this achievement. Practical design recommendations for designers who want to build effective, ethical user-centered digital applications can be derived. Gamification needs to be thoughtful. The user interaction analysis revealed that apps use two different methods to engage users by either providing only information or using gamified elements. However, as it was discussed in the literature review and confirmed by user reviews, gamification does not automatically lead to success, and as a persuasive tool, it risks falling into manipulation, potentially creating an inauthentic connection with users and raising ethical concerns [50]. The topic modeling results showed that users like interactive features (Topic 1) but user interaction needs to be based on purposeful grounds and aligned with the sustainability goals of the app [51]. App reliability depends not only on ethical design, but also functionality. Ethical persuasion and technical stability are needed to bring about behavior change. A poorly functioning app, no matter how well-intentioned, will eventually fail in delivering its persuasive goals. Ethical persuasive design must thus be accompanied by a strong foundation of usability, stability, and accessibility. Autonomy and transparency must be part of persuasive strategies. In the literature about persuasive technology it was emphasized how there is an emerging concern about the ability to differentiate between influence and manipulation [52]. Users expect clear disclosure about the methods and reasons behind behavioral influence through strategies such as nudging, gamification, and social comparison. The need for transparency, apart from being strongly supported by the literature, is also indirectly reflected through user feedback as observed in the topic modeling results that emerged in Topic 2. Users respond positively to concrete climate-related impact. The third Topic generated from topic modeling demonstrated how users value actionable assistance for environmental behavior. From carbon tracking to supporting reforestation or food waste reduction efforts, users tend to value more the applications that integrate straightforward metrics for indicating the impact that they are having to achieve the improvements they strive for in protecting the environment. Designers should create features that convert general sustainability targets into concrete, measurable activities that motivate users while providing a clear understanding of how their actions actually benefit the environment. Informational value is a driving force in consumption-related apps. As observed through Topic 4 of topic modeling, users frequently interact with apps that allow scanning, rating, and comparing food and consumer products. Developers in this space of the sustainability apps landscape should focus on achieving database accuracy, transparency or ratings, and user interface elements that help them make informed choices in real-time shopping environments. Accessibility and cost sensitivity must not be ignored. For this guideline, the existing literature does not directly address it, however the reason for including it is based on the fifth Topic 5 emerging from the topic modeling analysis, where users expressed concerns about affordability, and ethical shopping decisions. Applications must provide affordable solutions to sustainability actions to onboard lower-income users. Sustained user engagement should be encouraged. Widespread involvement requires dynamic problems, responsive feedback and rewards that address sustainability aims. As discussed in the literature, short-term behavior shifts are common, but long-term transformation is rare unless continuously supported by the app’s design. Designers should consider incorporating adaptive feedback, evolving challenges, streak tracking, and meaningful rewards to foster prolonged interaction, while still aligning with sustainability goals. Designers should involve diverse users in participatory design processes and adopt culturally sensitive approaches that respect different values, behaviors, and environmental challenges. The design guidelines presented at the end are one of the most important outcomes of this research. These suggestions are based on actual user feedback and app performance patterns observed in this study. They demonstrate that while certain elements, such as gamification or impact tracking, can be effective, their success really depends on how well they are implemented. VII. Conclusion This thesis investigated the evolving relationship between mobile technologies with environmental sustainability through an analysis of 54 sustainability-focused mobile applications listed on the Google Play Store. The research evaluated sustainability app design while assessing their effectiveness through both design and user experience perspectives. Through a layered methodology that combined app categorization, sentiment analysis, and topic modeling of user reviews, the research sought to understand how these apps engage users, how they are perceived once in use, and how they succeed (or not) in supporting long-term behavior change toward environmental goals. The research findings demonstrate that the landscape for mobile sustainability applications may be rich in variety, but quality-wise it remains inconsistent. Numerous apps are populating the market for digital sustainability advocacy, indicating rising innovation and user engagement in this sphere. However, their effectiveness and ethical standards differ substantially. The design guidelines produced from this study integrate these findings into a practical framework that designers and developers can use to create more effective and ethically sound sustainability applications. App designers should focus on building systems that establish trust while respecting user autonomy as primary goals, to succeed in providing genuine support for sustainable behavior adoption instead of concentrating solely on engagement metrics and visual design. The provided insights work to transform sustainability app design discussions from basic engagement metrics to focus on creating substantial environmental impact through measurable and enduring results. This study provides a paradigm of mixed methodology that leans on user-centered design and NLP-based analysis by combining app categorization, sentiment analysis, and topic modeling to create a scalable mixed-method approach for evaluating sustainability apps that integrates system-level design perspectives with user-generated feedback. Sustainability apps are becoming very influential but have to strike a balance between innovation, ethics and transparency; however, their success depends on the design choices designers make and their willingness to create apps with purposeful design and user empowerment, as these are crucial foundations based on the existing literature. The findings show that apps need to be both innovative and engaging while maintaining transparency, inclusivity, and using ethical persuasive methods to build a more sustainable future. Future research must include cultural variations, long-term user loyalty, and co-design procedures in scarcely supported areas. DECLARATION Funding: There was no funding Clinical Trial Number: not applicable. Consent to Publish declaration: not applicable. Consent to Participate declaration: not applicable. Ethics declaration: not applicable. Conflict of Interest: There was no conflict of interest IX. Author contribution EC: The project was conceptualized and designed, data was gathered and analysed, and the author prepared the manuscript. EC: The individual provided assistance in the collection and analysis of data, made contributions to the interpretation of the results, and conducted a critical review of the paper. EZ: The individual offered assistance in the development of the research methodology and the interpretation of the collected data. Additionally, critically evaluated and revised the work to enhance its intellectual substance. EZ: Participated in data collection, reviewed the literature, and contributed to the manuscript's writing and editing. 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SDG 12 (Responsible Consumption), SDG 8 (Decent Work and Economic Growth) Sustainable Lifestyle and Habit Building Encourages eco-friendly habits via tips and challenges SDG 12 (Responsible Consumption), SDG 3 (Good Health and Well-being) Sustainable Mobility and Transport Promotes low-carbon travel with gamified incentives SDG 11 (Sustainable Cities), SDG 13 (Climate Action) Food Sustainability and Waste Reduction Supports sustainable eating and food waste reduction. SDG 2 (Zero Hunger), SDG 12 (Responsible Consumption), SDG 13 (Clima Action) Circular Economy and Recycling Motivates recycling and reuse through rewards and education. SDG 12 (Responsible Consumption), SDG 9 (Industry, Innovation and Green Finance and Business Sustainability Focuses on ethical investing and green business strategies. SDG 9 (Industry and Innovation), SDG 8 (Decent Work), SDG 13 (Climate Action) Community Engagement and Social Platforms Builds communities around shared environmental action. SDG 17 (Partnerships), SDG 11 (Sustainable Cities), SDG 13 (Climate Action) TABLE II. Categorization of Sustainability Apps App Name Gamified Informative Reviews Thematic Focus Green the Planet / 2 Yes Yes Yes Environmental Awareness and Education (4, 13) Earth Hero: Climate Change Yes Yes Yes Environmental Awareness and Education (4, 13) Go Green Challenge Yes Yes Yes Sustainable Lifestyle and Habit Building (12, 3) Green Point: Food & Cosmetics Yes Yes No Circular Economy and Recycling (12, 9) My Green City Yes No No Environmental Awareness and Education (4, 13) Green Money Yes Yes No Green Finance and Business Sustainability (9, 8, 13) Ganddee Yes Yes No Community Engagement and Social Platforms (17, 11, 13) Earth5R Yes Yes Yes Sustainable Consumption and Product Transparency (12, 8) Continues… TABLE III. Overview of App Distribution by User Interaction Type, Review Availability, and Thematic Focus User Interaction Type App Count Percentage (%) Gamified Informative Both gamified and informative 7 17 30 12.96% 31.48% 55.56% Total (User Interaction Type) 54 100% App Review Availability App Count Percentage (%) Apps with reviews Apps with no reviews 21 33 38.89% 61.11% Total (User Interaction Type) 54 100% Thematic Focus App Count Percentage (%) Environmental Awareness and Education Carbon Footprint Tracking and Climate Action Sustainable Consumption and Product Transparency Sustainable Lifestyle and Habit Building Sustainable Mobility and Transport Food Sustainability and Waste Reduction Circular Economy and Recycling Green Finance and Business Sustainability Community Engagement and Social Platforms 11 13 10 8 2 4 5 2 5 20.37% 24.07% 18.52% 14.81% 3.70% \ 7.41% 9.26% 3.70% 9.26% Total (User Interaction Type) 54 100% Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7310678","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":507908515,"identity":"7701078b-2fb5-41fa-a62a-6b4f4b9ce894","order_by":0,"name":"Eva Cipi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2klEQVRIiWNgGAWjYLCCBAYJHjZm5gNApoQM0Vpk+NnZEkBaeIi2yEayn8cAxCCshV8i+eGHhzsseAwO83x+daPGgoeB/fDRDfi0SM5IM5ZIPCMB1MK7zTrnGNBhPGlpN/BpMThzwIwhsQ2ixTiHDahFgscMrxb7M8e/QbXwPDPO+UeEFgP2Hogtks08zI9z24jQInG8pxjsF35mNjPm3D5gBBHyC38z+8aPP3fU2bPxH378OedbnRw/++FjeLWAAWMDmGKTAJMElSNpYf5AlOpRMApGwSgYcQAASsRAABmAVEYAAAAASUVORK5CYII=","orcid":"","institution":"University Epoka","correspondingAuthor":true,"prefix":"","firstName":"Eva","middleName":"","lastName":"Cipi","suffix":""},{"id":507908516,"identity":"31fa53a1-61d2-4ad0-b69b-ade9e579ec92","order_by":1,"name":"Eljona zanaj","email":"","orcid":"","institution":"University Epoka","correspondingAuthor":false,"prefix":"","firstName":"Eljona","middleName":"","lastName":"zanaj","suffix":""}],"badges":[],"createdAt":"2025-08-06 14:23:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7310678/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7310678/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":90387118,"identity":"ff0e127d-dd31-4eb8-a1a7-fc47051667fb","added_by":"auto","created_at":"2025-09-02 07:45:05","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":59371,"visible":true,"origin":"","legend":"\u003cp\u003eWeighted average user sentiment scores for each app by category. Dots represent individual apps, colored by interaction type. Black crosses (X) indicate the weighted mean sentiment score within each category.\u003c/p\u003e\n\u003cp\u003eWeighted average user sentiment scores for each app by category. Dots represent individual apps, colored by interaction type. Black crosses (X) indicate the weighted mean sentiment score within each category.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/697c6557f2be84dcc1030413.png"},{"id":90387116,"identity":"a31c1945-e834-446a-b728-99178d8bd7f4","added_by":"auto","created_at":"2025-09-02 07:45:05","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":65566,"visible":true,"origin":"","legend":"\u003cp\u003eIntertopic Distance Map highlighting Topic 1.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/4a2f2e54de5657cccb32d1c1.png"},{"id":90387117,"identity":"e9de9fea-2834-4bc5-83d6-af63d3778e55","added_by":"auto","created_at":"2025-09-02 07:45:05","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":60335,"visible":true,"origin":"","legend":"\u003cp\u003eIntertopic Distance Map highlighting Topic 2\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/9b81792bdb97211fba5720e9.png"},{"id":90388486,"identity":"cf1ac6ed-f87c-40f3-8597-c9ca61f17f81","added_by":"auto","created_at":"2025-09-02 08:01:05","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":51500,"visible":true,"origin":"","legend":"\u003cp\u003eIntertopic Distance Map highlighting Topic 2\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/dd7056fdc6271476fc28f3bd.png"},{"id":90387459,"identity":"6ea244f1-cd3e-40c6-bf0f-c979989a03a5","added_by":"auto","created_at":"2025-09-02 07:53:05","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":53784,"visible":true,"origin":"","legend":"\u003cp\u003eIntertopic Distance Map highlighting Topic 4\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/860999c5025cc03f19710ab5.png"},{"id":90388487,"identity":"2efe1a5c-ded1-49bf-bd03-0471fb8ac39c","added_by":"auto","created_at":"2025-09-02 08:01:05","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":60742,"visible":true,"origin":"","legend":"\u003cp\u003eIntertopic Distance Map highlighting Topic 5\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/d9ac6b12fb7515d26207948d.png"},{"id":100239895,"identity":"6dfc5557-578b-4e07-9be4-28e67ed1b726","added_by":"auto","created_at":"2026-01-14 13:10:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1485122,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7310678/v1/b54d7604-efa3-47eb-b3a8-6b2533c26b2e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Design Insights from Sustainability Apps to Guide User Centered Mobile Application Development","fulltext":[{"header":"I.\tINTRODUCTION","content":"\u003cp\u003eMobile apps have evolved into highly complex systems that not only change human behavior in an individualistic manner but also collectively. They have influenced the personal sustainability participation by using educational materials that monitor the behavior, and they also offer motivation to green actions. The digital solutions are now applicable to the climate change and environmental degradation struggle in two ways: promoting sustainable practices, developing communal participation, and maintaining the citizen science program.\u003c/p\u003e\n\u003cp\u003eMobile applications can also be the part of the solution of environmental concerns with the help of conservation, waste and sunshine use activities [1, 2]. They have developed a combination of educational materials with interactivity and promotional strategies to make such an approach an innovative environment that allows coming together of technological novelty and the protection of the environment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe job of the mobile applics as the facilitators of sustainable behavior is monitored in several correlated ways. The rapid technological development coupled with changes in user needs, however, creates obstacles to the evaluation of the long-term consequences that cannot be neglected. Assessing an app based only on the isolated mechanism of accessing pure user review can potentially subject the entire exercise to potential misleading outcomes and incompleteness. Consumer rating is typically done on convenient answers or mainstream branding as opposed to a long-term impact. User feedback contains valuable information yet needs systematic evaluation to extract significant patterns while preventing broad interpretations. Contrary to digital health, there is no standard model in which to analyze user data in sustainability app assessment [3]. This gap points to the need for more nuanced and multidimensional methods that can account for the complex relationship between app features, user experience, and environmental impact.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBased on the current trends, digital sustainability is depicted as capitalizing on advanced analytics and machine learning to provide customized recommendations and immediate feedback. In addition, these applications transform into community empowerment platforms that enable collaborative governance and connect individual actions to broader policy objectives. One example that could be given is The Internet of Things (IoT)—once merged with mobile technology, it allows for detailed environmental metric tracking that leads to improved transparency and accountability [4]. The development and implementation of these technologies are now heavily focused on ethical aspects, such as data privacy, user consent, or transparency without them due to the greater social awareness of social consequences [5].\u0026nbsp;\u003c/p\u003e"},{"header":"II.\tLITERATURE REVIEW","content":"\u003cp\u003eResearch studies have investigated different aspects of mobile applications for sustainability by studying their design elements and engagement mechanisms, as well as their ability to create enduring positive behavioral shifts. Although gamification is associated with motivation, such approaches have not been used uniformly in sustainability applications on phones [6]. Other than being entertaining alone, it should also encourage pro-environment behavior.\u003c/p\u003e\n\u003cp\u003eThe broad variety of the design strategies and user motivation methods results in applications serving as sources of information or systems that employ persuasive mechanisms through challenges, rewards and tracking progress as behavioral regulators. Although such variations can provide valuable data regarding the advocacy of digital sustainability, the difficulty in evaluating and comparing apps on a set of standardized criteria persists. This lack of formal guidance has led to an uncomfortable standstill in the process of moving forward to adopt a green mindset in which we are to act consciously or we will never thrive with the environment. Developers need to get over their green rhetoric and start writing apps that really promote sustainable behavior.\u003c/p\u003e\n\u003cp\u003eThe guide is intended as a stepping stone to more thoughtful app designers and can be regarded as a means to an inspiration as opposed to a list of what is best. It prompts some questions such as: What is the type of behaviour we are encouraging? Do our gamification methods have any significance or are they just garnish? Or are we helping in the autonomy of the users, or are we pushing them too hard?.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eA. The Concept of Sustainability in Mobile Apps\u003c/h2\u003e\n\u003cp\u003eRecent research findings challenge the traditional theory on the nature of mobile apps as inanimate tools and prove their capability of dynamic modification of human behavior. One paper pointed out that apps do not serve existing human objectives but rather ally themselves with other systems, leading to unanticipated interactions and having the potential to transform habits fundamentally [7]. This new perspective holds fundamental importance in sustainability considering mobile apps for sustainable mobility, waste management, and green food practices can reconfigure how people handle resources and protect the environment [8, 7; 9].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThere has been conducted extensive research also on persuasive technology which functions as a mechanism to promote desired behavioral modifications. The Persuasive Systems Design (PSD) model presents a detailed framework that explains how mobile apps can influence users toward sustainable behavior adoption [8]. Waste management applications utilize reduction and personalization alongside tailoring and self-monitoring persuasive strategies to reduce user effort in target behaviors while providing ongoing feedback [9]. The research demonstrates users will interact extensively with systems that deliver appropriate guidance to reach behavioral targets and deliver individualized information that supports knowledge absorption through clear explanations.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe research on energy efficiency, the inclusion of sustainability as a quality parameter for Information Technology and Systems, as well as as other variations uncovering the connection between software engineering and green practices have been predominantly more extensive than the more granular work needed specifically for applications [10; 11; 12;13;14;15;16; 17; 18; 19; 20]. The latter has been seemingly sporadic over the last decade and has gained more traction only the recent years. Service-oriented software development typically starts with unlimited resource assumptions but real-world data centers use energy that exceeds what tens of thousands of households would consume [21].\u003c/p\u003e\n\u003cp\u003eResearch has demonstrated how mobile applications support sustainability efforts across waste management, green food practices, and sustainable travel behavior [22; 23; 24]. Different applications have unique priorities since they provide either advanced monitoring capabilities or they embed sustainability features into popular mainstream applications to provide users with better convenience and encourage eco-friendly behavior [24; 25].\u003c/p\u003e\n\u003ch2\u003eB. Gamification as a Catalyst for Sustainable Behavior\u003c/h2\u003e\n\u003cp\u003eThe Gamification as a preferred design strategy for digital advocacy applications seems extremely promising as a way to foster user engagement while influencing behavioral patterns. Developers embed game elements such as badges and leader--boards into routine applications to create an entertaining experience for users that helps boost user retention as well as extend app longevity [26]. The application of gamification techniques in sustainability efforts targets the promotion of recycling, energy conservation, and responsible consumer behavior. A research study by [27] showed that gamified challenges led users to experience both higher enjoyment and knowledge acquisition, which resulted in real behavioral transformations. Different gamification features generate different impacts on behavioral shifts.\u003c/p\u003e\n\u003cp\u003eAnother study found support for the conclusion that some gamified interventions sometimes fail to reduce resource consumption but other approaches show potential in speeding up environmentally responsible actions. This study establishes how gamification requires sophisticated understanding to achieve lasting behavioral shifts and demonstrates the need to identify effective game design features [28].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGamification should not aim to make sustainability more palatable by simply reshaping existing consumption patterns. Rather, it should support a deeper transformation in how users relate to sustainability\u0026mdash;as a lifestyle, not just a feature [29].\u003c/p\u003e\n\u003ch2\u003eC. Current Evaluation Criteria for Mobile Apps\u003c/h2\u003e\n\u003cp\u003eFor assessing sustainability applications we need to use diverse evaluation methods. Research studies have evaluated digital tools through usability metrics and user engagement indicators along with behavior change models. The research on gamification and persuasive technology delivers essential knowledge about digital interventions that affect user motivation. Users remain doubtful about sustainability claims unless digital tools demonstrate transparent methodologies and obtain third-party certifications [30].\u003c/p\u003e\n\u003cp\u003eMobile sustainability applications require a specialized evaluation framework that has not been developed yet, differnetly from health and education mobile apps which, as we have already mentioned, have been subject to more extensive research. Health evaluation frameworks have experienced substantial growth because they offer standardized methods to evaluate usability, privacy, clinical effectiveness, and overall app quality [31]. Mobile applications are evaluated using multidimensional rating systems, including MARS and its derivatives which combine content validity with user experience and data privacy assessment [32]. Sustainable mobile applications need an established evaluation framework because they face similar challenges from rapid innovation and frequent updates alongside balancing technical performance against behavioral impact. Researchers demand a complete assessment framework that unites multiple domains such as content validity, user experience, engagement, interoperability, technical features, and privacy into one unified structure [32].\u003c/p\u003e\n\u003cp\u003eThe literature emphasizes that user-centric design and culturally specific development approaches are essential for sustainability app creation. Users currently favor sustainability features which are integrated into widely used apps instead. The research evidence demonstrates the importance of involving end users in co-design activities for developing apps because it ensures these applications match their daily habits along with their personal tastes and cultural backgrounds [33]. Users are largely excluded from the development phase of both software and applications.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs final remarks, the research shows an entanglement of initial efforts into exploring specifically gamification technology, persuasive design methods, and mobile platforms for reaching sustainability targets. The field has achieved substantial progress, but this does not indicate that major gaps in knowledge do not continue to persist. The greatest part of current research about gamified apps neglects to study the complete range of sustainability applications.\u003c/p\u003e"},{"header":"III. EXPLORING DESIGN PRINCIPLES FOR SUSTAINABLE MOBILE APPLICATIONS","content":"\u003cp\u003eMobile applications that immerse into sustainability challenges need their design to match usability and engagement targets while fulfilling environmental and ethical requirements. The following section combines sustainable and green UX/UI design best practices with mobile app design and user-centered ethics guidelines based on industry reports, design agencies, and expert blog publications.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eA. Minimizing Environmental Impact through User Experience\u003c/h2\u003e\n\u003cp\u003eAs a first step, sustainable design requires an application to have a reduced digital and environmental footprint. This is achievable by optimizing User Experience (UX), to decrease energy consumption and processing power usage. An example of what can be categorized as UX optimization is using weight reduction techniques for the minimization of high-resolution multimedia elements like images, videos, and complex animations, enabling applications to achieve both faster loading speeds and decreased data usage. Subsequently, CO emissions associated with data transfer and processing are reduced considerably [34].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThere is another article that supports the idea of using compressed multimedia assets and also provides additional ways to converge to mindful app design, including efficient coding practices and app bloat reduction. Users are enabled in this way to finish tasks through fewer clicks and navigation steps, reducing their screen time and energy usage. These methods ensure an improvement in ecological efficiency while also enhancing user satisfaction [35]..\u003c/p\u003e\n\u003ch2\u003eB. Balancing Engagement and Sustainability\u003c/h2\u003e\n\u003cp\u003eSustainable app design is expected to create a balance between engagement strategies and ethical as well as environmental concerns. The implementation of gamification and habit loops for user retention improvement requires careful consideration. An exclusive focus on engagement can marginalize sustainable practices, leading to increased device usage, push notification fatigue, and superficial reward systems that further promote consumerism. This is, in fact, supported by the literature, as discussed in the respective section, which highlights how certain efforts can backfire\u0026mdash;hindering genuine change by reinforcing the very sources of the problem [36].\u003c/p\u003e\n\u003cp\u003eDesigners should implement mindful interactions that help users achieve their goals without creating distractions or excessive resource consumption. Users gain control over their experience through customizable notification preferences, energy-saving features, and data collection transparency that enables them to make conscious choices regarding their preferences [37].\u003c/p\u003e\n\u003ch2\u003eC. Behavior Change Design Techniques Beyond Gamification\u003c/h2\u003e\n\u003cp\u003eThe popularity of gamification for user engagement in sustainability apps should not overshadow the fact that behavior change design uses multiple strategies which extend past game mechanics. Sustainable mobile applications can use the five key themes of the Behavior Change Strategy Cards developed by Artefact Group to implement various techniques that enable ethical and holistic influence on user behaviors [38].\u003c/p\u003e\n\u003cp\u003e● \u0026quot;Make It Personal: The Persuasive Power of \u0026rsquo;Me\u0026rsquo; and \u0026rsquo;My\u0026rsquo;\u0026quot;. The process of personalization makes sustainability goals and actions more relevant and motivating through individualized framing. The approach includes tailoring feedback to match user-specific contexts and habits, encouraging self-monitoring and reflection, as well as goal creation that aligns with one\u0026rsquo;s own personal beliefs.\u003c/p\u003e\n\u003cp\u003e● \u0026quot;Tip the Scales: How Perceptions of Losses and Gains Influence Our Choices\u0026quot;. This category leverages insights from behavioral economics by framing choices to highlight perceived gains or losses. The way this works is that apps can use two different approaches to encourage the adoption of sustainable behavior: either by showing users the advantages of sustainable actions (health benefits and cost reductions), or the negative outcomes of inaction (environmental harm and resource waste).\u003c/p\u003e\n\u003cp\u003e● \u0026quot;Craft the Journey: Why the Entire Experience Matters\u0026quot;. It is understood in this present context that behavior change does not occur via disjointed individual interactions. It, instead, requires an effective user journey. This process requires the simplification of difficult tasks and the ability to provide a clear representation of progress made, and it also incorporates educational materials that can illustrate the impacts of behavior in the environment.\u003c/p\u003e\n\u003cp\u003e● \u0026quot;Set Up the Options: Set Up the Options to the Desired Decision. Choice architecture is a process that serves as an instrument that guides the users towards sustainable decisions. Designers are supposed to make green choices the default choice and decrease choice overload by limiting arbitrary decisions and adding mental reminders or triggers at decision points.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● \u0026quot;Keep It Simple: Avoiding Unwanted Result. The problem with behavior change is that individuals are more likely to get stuck when they have faced situations that are complex or daunting. When the interfaces are simplified and barriers as well as interruptions are either minimized or averted, users keep on being motivated and consistent.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eD. Green IT and Sustainable Development Practices\u003c/h2\u003e\n\u003cp\u003eShifting the lens beyond the interface, backend operational practices are also responsible for affecting the environment. The implementation of green IT strategies that support digital sustainability includes practices such as selecting a host server that is powered by renewable energy, reducing server load, and using efficient databases and APIs [39]. Additionally, mobile developers are encouraged to monitor the environmental impact of their products throughout time, by using tracking tools to measure energy consumption and digital carbon emissions.\u003c/p\u003e\n\u003ch2\u003eE. Ethics and Inclusivity\u003c/h2\u003e\n\u003cp\u003eDespite it being intuitive, it is important to be explicit in stating that green design does, indeed, stand in both social and ethical dimensions. The \u0026ldquo;Society-Centered Design\u0026rdquo; movement and \u0026ldquo;Climate Designers\u0026rdquo; network state that ethical technology must protect user rights while making products accessible to them and building community empowerment [40].\u003c/p\u003e\n\u003ch2\u003eF. Green Design Trends in Practice\u003c/h2\u003e\n\u003cp\u003ePractical applications of green technology serve as additional evidence that demonstrates how \u0026nbsp;the mentioned principles become actualized. The user interfaces of \u0026ldquo;Energy Saver\u0026rdquo;, \u0026ldquo;EcoBuddy\u0026rdquo; and \u0026ldquo;Gaia\u0026rdquo; demonstrate minimalism through restrained colors while maintaining efficient features that prevent digital and cognitive strain [41]. These apps witness how sustainable design is achieved by preserving both user satisfaction and aesthetic appeal, thus without the need to compromise either element with the purpose of affecting the environment as little as possible. The combination of dark mode functionality with local caching and carbon awareness indicators in the interfaces enables users to track and manage their digital carbon footprint. Such features combine practical functionality with educational elements that lead users toward sustainable practices by implementing sustainability principles throughout their usage journey.\u003c/p\u003e"},{"header":"IV.\tMETHODOLOGY","content":"\u003cp\u003eThis research is driven by adopting an exploratory approach to analyze existing mobile applications that promote sustainable behaviors. A systematic selection and categorization of the relevant apps from the Google Play Store is the first building block of this methodological process, aiming to form a curated dataset of mobile tools aimed at supporting green practices. Rather than conducting a mere traditional content analysis, this phase integrates both qualitative and computational techniques for enriching the understanding about the effectiveness of the collected apps, user perceptions, and engagement dynamics. This analysis sets the foundation for developing informed recommendations that may guide app designers in enhancing digital advocacy for environmental sustainability.\u003c/p\u003e\n\u003ch2\u003eA. \u0026nbsp;Platform Selection and Search Terms\u003c/h2\u003e\n\u003cp\u003eGoogle Play Store was chosen because of its accessibility, open publishing, and extended developer reach. Android devices rule the global smart phone market, especially in regions that favor affordable open-source platforms. It has a quick review and open nature, which attracts many developers, including those in the emerging markets, to publish sustainability-related applications. The lower barrier to entry on the Play Store often results in a wider array of app types, including niche or experimental green initiatives that may not pass the stricter quality control of the Apple ecosystem. The open nature of this platform works well with research exploration because it enables an extensive evaluation of digital environmental advocacy tools.\u003c/p\u003e\n\u003cp\u003eFor the sake of broad and relevant coverage, two primary search terms were used:\u003c/p\u003e\n\u003cp\u003e● \u0026nbsp;“Green”\u003c/p\u003e\n\u003cp\u003e● \u0026nbsp;“Sustainab-”\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis choice reflects a strategic departure from another research study, which used only one term due to constraints in their search strategy, considering the two interchangeable [42].\u003c/p\u003e\n\u003ch2\u003eB. Application Selection Criteria\u003c/h2\u003e\n\u003cp\u003eThe process of selection of applications for the research was designed to be fair and retain significance using an approach that balanced reach, relevance and reliability. The final analysis is based on apps that meet several pre-defined inclusion criteria. Establishing these requirements guaranteed total transparency and maintained integrity throughout the entire selection process. The first practical criterion evaluated the availability of language support. Only English and Italian apps were chosen to make correct qualitative analysis of the researcher. The selection of apps with English or Italian language support allowed both interface and content interpretation, and also enabled a more nuanced qualitative evaluation of its tone, messaging, and functionality. \u0026nbsp;Beyond language, the applications also needed to demonstrate relevance and engagement in one of the three key ways to qualify for study participation. Indicating a certain download volume will be helpful to notice whether an app has achieved notable public visibility and user engagement, establishing its relevance in the sustainability app market.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTo make sure the apps selected for this study had a meaningful level of public engagement, a threshold of 10,000 downloads was used. The selection choice followed the research approach of another body of work which established this benchmark to evaluate health apps because it demonstrated their visibility and meaningful user interaction .\u003c/p\u003e\n\u003cp\u003eRegarding external recognition, the inclusion of apps depended on their validation through partnerships with credible organizations, certifications, or endorsements from subject matter experts, which added credibility to their selection. The inclusion logic for app selection can be formalized as follows, This reasoning was motivated by assessment criteria applied in the evaluations of digital health apps proposed by Henson et al (2019):\u003c/p\u003e\n\u003cp\u003eInclude App →↑ Language ↓ {English, Italian}\u003c/p\u003e\n\u003cp\u003e↔ (Downloads \u0026gt; 10,000 ↗ Strong Sustainability Focus ↗ Expert Approval)\u003c/p\u003e\n\u003cp\u003eAn override condition was applied in cases where apps had no downloads. Specifically:\u003c/p\u003e\n\u003cp\u003eIf Downloads = 0 ↔ Strong Sustainability Focus ↑ Manual Inspection\u003c/p\u003e\n\u003cp\u003eIn other words, apps with zero downloads but demonstrating a strong sustainability focus were manually evaluated to determine their relevance and potential inclusion.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eC. Observations and Exclusions\u003c/h2\u003e\n\u003cp\u003eDuring the app selection process multiple specific patterns emerged, which determined the final composition of the dataset. These findings proved important for the methodology while also revealing significant problems that exist in sustainability apps regarding branding deception, limited scope and concerns about long-term relevance. Many applications emerged to fulfill particular narrow use cases which dominated the market. Two examples of complementary applications can be \"Green Drive\" which assists car users and \"Sustainable Ocean Alliance\" which concentrates on ocean environmental initiatives. The search results showed that keyword selection played a major role during the investigation. The search term “green” yielded many applicable apps yet most of these results also appeared when using the more effective “sustainab-” keyword, which, as we already discussed, encompasses “sustainable” and “sustainability”. The search term “green” yielded only five relevant results that also appeared in the “sustainab-” search results. The selection of the “sustainab- ” keyword became the final criterion to build the list of 54 apps. Using only the “sustainab-” keyword for the selection process improved efficiency while demonstrating the value of selecting appropriate search terms for systematic reviews.\u003c/p\u003e\n\u003ch2\u003eD. Keyword Electiveness and Relevance\u003c/h2\u003e\n\u003cp\u003eThe entire search process through app stores heavily depended on metadata and keyword matching which made success dependent on the quality of selected terms that matched sustainability-related digital tools. Three different keywords received initial testing to investigate sustainable apps which included \"green,\" \"sustainab-\" and \"environment.\" Among these three keywords the keyword \"sustainab-\" delivered the most relevant results because of its high number of quality search outcomes. Using the root term \"sustainab-\" which encompasses terms such as \"sustainable\" and \"sustainability\" brought forth the most significant number of apps that might match study criteria.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eShifting the focus to the results obtained from the search conducted based on the keyword \"green\", it can be observed that there is an inconsistency in comparison to the other two key words.\u003c/p\u003e\n\u003ch2\u003eE. Categorization by User Interaciton Strategy\u003c/h2\u003e\n\u003cp\u003eThis application categorization is defined based on the main user interaction method employed, which relies predominantly either on game-like mechanisms or the delivery of informative content working as different motivational approaches to encourage user participation. Thus, one of the focal points of the classification process was separating applications according to their strategy of interaction, i.e., whether they employ gamification or adhere to a more informative mode. Also, engagement will be used interchangeably with interaction in this section.\u003c/p\u003e\n\u003cp\u003eGamified apps are designed to be engaging and fun, borrowing from video games in an effort to encourage regular use. Such features can be as straightforward as awarding points, unlocking badges, completing levels or missions, maintaining streaks, or climbing leaderboards. Others include avatars or interactive stories. Actually, some apps incorporate aspects of both types. In such instances, a decision was made regarding the predominant mode of interaction.\u003c/p\u003e\n\u003ch2\u003eF. Categorization by Review Availability\u003c/h2\u003e\n\u003cp\u003eThe second main criterion on which the shortlisted applications were classified was whether they have received any user reviews from real users on the Google Play Store. To go beyond basic observations into deeper insights regarding the preferences and dislikes of users related to how apps fit into their sustainable lifestyles, the applications were sorted into two main categories:\u003c/p\u003e\n\u003cp\u003e● Apps with reviews: Representative of apps having either ratings, written feedback, or both. This is an extremely helpful subset of the dataset since they reflect first-hand user experience\u003c/p\u003e\n\u003cp\u003e● Apps without reviews: Representative of apps that had not yet been downloaded by users or had the review feature disabled for some unknown reason.\u003c/p\u003e\n\u003cp\u003eBy separating apps into those with and without reviews, this categorization ensures that the evaluation remains grounded in real-world usage wherever possible.\u003c/p\u003e\n\u003ch2\u003eG. Categorization by Thematic Focus\u003c/h2\u003e\n\u003cp\u003eThe final dimension of categorization involved the thematic content of each app, referring to the type of sustainability issue it sought to address. The categories can be observed through Table \u0026nbsp;1. To deepen this thematic analysis by connecting it with global priorities, and also create more familiarity with the themes, the app categories were mapped to the United Nations Sustainable Development Goals (SDGs) [43]. Mapping the apps to relevant SDGs allowed for a clearer understanding of how digital solutions align with broader sustainability frameworks.\u003c/p\u003e\n\u003cp\u003eThus, these categories illustrate the various types of digital solutions that can be used to promote sustainable conduct. The apps are flexible in their reach regarding target audience. All users–be them beginners in building sustainable habits or deeply committed to an eco-friendly lifestyle–can benefit from these apps which serve as valuable resources offering information, motivation, and opportunities to connect with the ones who share the common goal of creating a more sustainable world.\u003c/p\u003e\n\u003ch2\u003eH. Sentiment Analysis of User Reviews\u003c/h2\u003e\n\u003cp\u003eThe evaluation of mobile applications focused on sustainability requires knowledge about how users experience and use these digital tools. This research uses sentiment analysis as a widely recognized Natural Language Processing (NLP) technique to extract meaningful patterns from review data. The fundamental purpose of sentiment analysis is to enable researchers to automatically assess whether user-generated content gravitate toward a positive, neutral, or negative sentiment. The analysis focused on sustainability applications with Google Play Store user reviews from the selected 54 applications. The information structure includes the category, a short description and relevant SDGs as it is is presented at the Table 1.\u003c/p\u003e\n\u003cp\u003eThe sentiment analysis was conducted by making use of the VADER (Valence Aware Dictionary and sEntiment Reasoner) tool which operates as part of the Natural Language Toolkit (NLTK) in Python. To retrieve the review data, the Google Play Scraper Python library was employed. While the function was configured to retrieve up to 500 of the most recent reviews per app, the actual number of available reviews varied significantly across the sample. The number of reviews on some apps reached only five or six while other apps had received between 400 and 500 reviews. This difference in number of reviews stems from natural variations between apps regarding their popularity, user interaction, and the time available in the market.\u003c/p\u003e\n\u003cp\u003eThe text of each review was then processed by VADER, which produced a compound sentiment score ranging from -1 (extremely negative) to +1 (extremely positive). These scores were averaged per app to obtain an overall sentiment value, which was then categorized into positive, neutral, or negative based on standardized thresholds: scores above 0.05 were labeled as positive, those below -0.05 as negative, and values in between were considered neutral. To reiterate, despite the sample size limitation, this sentiment analysis represents a valuable first step in understanding how sustainability apps are perceived by their users in practice.\u003c/p\u003e\n\u003ch2\u003eI. Topic Modeling of User Reviews\u003c/h2\u003e\n\u003cp\u003eSentiment analysis gives useful information about user attitudes through emotional polarity measurement, however, it fails to identify the actual content of user discussions. For this reason the present study uses topic modeling as a second natural language processing (NLP) technique to analyze the specific themes, expectations, and concerns that users express in the reviews left for sustainability-focused mobile\u0026nbsp;Table 1\u0026nbsp;applications. Through topic modeling researchers can move past basic emotional assessments of user comments to detect hidden patterns in how people communicate about digital tools.\u003c/p\u003e\n\u003ch2\u003eJ. Data Collection and Review Preparation\u003c/h2\u003e\n\u003cp\u003eThe topic modeling analysis was conducted on the same dataset of user reviews used in the sentiment analysis phase. This included 21 sustainability apps (from the original set of 54) which had available English-language reviews on the Google Play Store. As with the sentiment analysis, the Python library \"google_play_scraper\" was used to collect up to 500 of the most recent reviews for each app. To ensure reliable linguistic consistency for the modeling process, once again only reviews in English were retained. The Python library \"langdetect\" was also used in this case to detect non-English entries that were then removed from the analysis. The topic modeling algorithm requires English-language data because as, similarly to VADER, it has been tested and optimized for content in English, and may struggle to interpret non-English text with sufficient semantic accuracy. The final dataset consisted of a consolidated corpus of English reviews distributed across the 21 selected apps, offering a balanced perspective from both widely used and more niche sustainability apps. The analysis became more robust by combining all filtered English-language reviews into one dataset. The collective modeling technique maintains user perspectives from various sustainability domains while revealing common themes and concerns which exist across different app in this landscape.\u003c/p\u003e\n\u003ch2\u003eK. Preprocessing for Topic Modeling\u003c/h2\u003e\n\u003cp\u003eExtensive cleaning and preprocessing had to be applied to the text corpus before the application of the topic modeling algorithm to enhance model clarity and performance. Each review was initially converted to lowercase, then it followed that the punctuation marks, numeric characters, and non-alphabetic symbols had to be removed. The Natural Language Toolkit (NLTK) was used to eliminate Standard English stopwords which include words like “and,” “the,” “is” since they do not contribute much semantic value. The Porter Stemmer was applied to each word to transform them into their base or root form (e.g., “distracted,” “distracting,” and “distract” all become “distract”). The process unified related concepts while decreasing the number of dimensions which proves essential when working with short and informal texts such as app reviews. The cleaned text had to finally go through its final layer of preprocessing, which is tokenization, to generate individual words before being organised in a manner that is compatible with topic modeling standards. The Gensim Dictionary class generated a dictionary of terms while doc2bow converted each review into the format of Bag of Words (BoW), used to determine how frequently were terms recurring in documents.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eL. LDA Modeling Implementation\u003c/h2\u003e\n\u003cp\u003eThe research applied Latent Dirichlet Allocation (LDA) because this established unsupervised machine learning method effectively extracts topics from text data and demonstrates reliability for NLP tasks with short-form user-generated content. The Gensim Python library served to implement the model. The final number of topics used in the research are five, after testing different topic counts between four and ten. The five-topic model achieved an optimal balance between thematic understanding and distinct topic separation. Probabilistic convergence of the model was guaranteed by ten passes. An important feature of LDA modeling is the lambda () parameter, which influences how words are ranked and interpreted within each topic. When = 1, the term ranking is based on overall frequency across all topics—highlighting the most common words. A λ = 0.4 gave much emphasis to topic-related terms and words and downplayed the generic ones, making thematic issues clear. The interpretation of topics through both values creates a dual perspective which reveals the general emotional or functional context ( = 1) and the specific conceptual nature of each topic ( = 0.4). To visualize topics and detect overlaps, pyLDAvis was utilised. This enabled an exploration of how the topics relate to one another spatially, the most salient terms for each topic, and the relative frequency and relevance of those terms. The interface allows a deeper inspection of each topic’s structure and is especially useful for identifying overlaps or potential ambiguities in topic boundaries.\u003c/p\u003e\n\u003ch2\u003eM. Integrating Topic Modeling in the Broader Analysis\u003c/h2\u003e\n\u003cp\u003eThe implementation of topic modeling together with sentiment analysis serves to create a fuller and more useful understanding of user experience. As sentiment scores measure emotional satisfaction, topic modeling reveals specific aspects to which users are reacting. Together, these tools provide a rich, complementary foundation for evaluating sustainability apps—not only in terms of how they make users feel, but also in relation to what users value, criticize, or recommend. The research approach, however, has certain boundaries that need to be recognized. The analytical value of topic modeling is arguably relevant, but several factors need to be taken into account. First, the number of reviews used, although filtered for quality and language consistency, remains modest due to the fact that not all sustainability apps receive substantial public feedback. Thus, the findings may not be generalizable, but they still provide useful qualitative insights into the recurring themes among users who are using these apps.\u003c/p\u003e\n\u003cp\u003eSecond, stemming and stopword removal—while improving model efficiency—may sometimes lead to the loss of contextual nuance, particularly in short user reviews. Yet, these steps were necessary to enhance model performance considering the unstructured and frequently disorganized nature of app store language.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFinally, the topics discovered are best interpreted as thematic cues rather than definitive categories. Their value lies in their ability to highlight user priorities and recurring issues that might otherwise be overlooked when evaluating app effectiveness solely based on numerical ratings or isolated comments. The Table 2 shows the four topics according to the sustainability categorization.\u0026nbsp;\u003c/p\u003e"},{"header":"V.\tRESULTS","content":"\u003ch2\u003eA. App Categorization\u003c/h2\u003e\n\u003cp\u003eIn this part initially presents the categorization outcomes and user review availability across the selected sustainability apps. The collection of 54 apps is displayed in Table 2 and it represents a wide range of thematic categories, offering valuable insights into how digital tools interpret and promote sustainability.\u003c/p\u003e\n\u003cp\u003eTable 3 illustrates the distribution breakdown in terms of all dimensions of categorization. A dominance of mixed interaction models is observed: more than half of the apps (55.56%) utilize both gamified and informative elements. The dataset consists of 31 percent informative, and 13 percent gamified-only apps. In terms of thematic focus, the most populated category is Carbon Footprint Tracking and Climate Action (24.07%). Then Environmental Awareness and Education follows (20.37%). Sustainable Consumption and Product Transparency (18.52%), which has strong links to SDG 12 (Responsible Consumption and Production), and Sustainable Lifestyle and Habit Building (14.81%), typically using gamified nudges to impact daily choices, are also themes that stand out. The presence of the Sustainable Mobility and Green Finance applications (each ~3.7%), indicates the new dimension of interest in SDG 11 and SDG 9.\u003c/p\u003e\n\u003cp\u003eAdditionally, having access to user reviews is useful to further enrich the analysis on app performance. A starking 61.11% of the collected apps do not have visible user reviews on the Google Play Store. The apps with reviews were used for the sentiment analysis and topic modeling presented in subsequent sections. Technology is being increasingly leveraged to conduct sustainabilityrelated efforts that aim to reflect progress in the areas targeted by the SDGs. This conclsuion is grasped through the intuitive yet layered analysis conducted so far.\u003c/p\u003e\n\u003ch2\u003eB. Sentiment Analysis Overview\u003c/h2\u003e\n\u003cp\u003eA summary table (4) was generated to show the number of reviews extracted for each app and the reviews that made it to the final analysis contribution stage after language filtering. This data is included to provide transparency about the amount of reviews that was used to calculate each sentiment score and to help to understand the results better. Each app is plotted in Figure 1 by average sentiment score (X-axis), theme category (Y-axis) and interaction type (bubble color and size) (based on compound VADER analysis) and grouping them vertically by thematic category. The analysis includes English language reviews which determine both the bubble size and color based on whether the app uses informative or gamified content, or both.\u003c/p\u003e\n\u003ch2\u003eC. Topic Modeling Overview\u003c/h2\u003e\n\u003cp\u003eThe LDA algorithm was used to analyze English-language user reviews through topic modeling for extracting deeper insights about user perceptions and priorities. The five generated topics consist of thematic clusters that show common user concerns, preferences, and sentiments about the sustainability apps studied.\u003c/p\u003e\n\u003cp\u003e● Topic 1: Engagement, Enjoyment, and Brand Enthusiasm This topic dominates the model with 31.6% of total token representation. It is positioned as the largest bubble in the upper-left quadrant of the pyLDAvis visualization and it also overlaps partially with Topic 3. What this means is that, these two topics share some shared thematic areas related to user appreciation and app enjoyment. Fig. 2\u003c/p\u003e\n\u003cp\u003e● Topic 2: Technical Frustrations and Usability Concerns The second topic contains 22.8% of tokens and appears as a medium-sized bubble in the lower left quadrant. The bubble remains near the main cluster (Topics 1 and 3) but presents a different story which apparently focuses on challenges and frustrations that users have experienced. Fig. 3\u003c/p\u003e\n\u003cp\u003e● Topic 3: Environmental Impact and Climate-Oriented Behavior Change. From topic 3, it can be seen that 21.9% of the total tokens are pertaining to it, and as already highlighted above, it overlaps with Topic 1, indicating shared themes. The bubble is located in the left part of the visualization and slightly above and to the left of Topic 1. The thematic connection between emotional satisfaction and sustainability driven motivation becomes evident through this overlapping area. Fig 4\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Topic 4: Food and Product Transparency. As for the fourth topic, it makes up 15% of the total corpus while located in the bottom left quadrant where it stands apart from the core cluster of Topics 1–3. The spatial distance indicates a clear conceptual boundary as this topic focuses mostly on food-related matters. Fig. 5\u003c/p\u003e\n\u003cp\u003e● Topic 5: Ethical Search, Pricing, and Eco-Friendly Shopping. \u0026nbsp;In the pyLDAvis map Topic 5 is shown as the smallest and most distanced topic, with only 8.7% representation out of the total tokens, being positioned in the top-right quadrant away from all other topics. What can be apprehended from the isolated position of this topic is that it represents a distinct thematic domain that is not strongly linked to the other user experiences seen so far. Fig. 6\u003c/p\u003e\n\u003cp\u003eThe topic modeling application on the reviews from the collected apps in this study provides a thematic map of what users value, praise, or critique in sustainability apps. The most dominant areas—Topic 1, Topic 2, and Topic 3—suggest that users are drawn to apps that are enjoyable, well-designed, and purpose-driven. These are the most prevalent areas to be addressed, however it is important to take into consideration also more niche priorities emerging among some of the discussions, such as health transparency (Topic 4) and cost-conscious browsing (Topic 5).\u003c/p\u003e\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"},{"header":"VI. Discussion","content":"\u003cp\u003eThe results are interpreted in this section with the help of previous studies in the field of persuasive design and digital sustainability. This section uses the literature review to reflect on the implications of the categorization patterns and sentiment analysis and topic modeling results for app designers and researchers who want to use mobile technology to promote environmental behavior. The study makes use of empirical data, building upon existing findings to propose practical insights which will help create more effective and ethically sound sustainability apps. The discussion begins by revisiting several important patterns from the app distribution analysis, especially the design approaches and interaction strategies that establish the foundation for a deeper examination of user experience, values, and motivation.\u003c/p\u003e\u003ch2\u003eA. Insights from App Categorization\u003c/h2\u003e\u003cp\u003eAs indicated in Table 1, the gamification phenomenon is common particularly in apps aiming to transform daily behavior, like the carbon tracking apps or lifestyle apps, with many apps incorporating challenges, point systems, streaks, and reward mechanisms—design elements previously discussed. When it comes to categories like Sustainable Lifestyle and Habit Building, and Carbon Footprint Tracking and Climate Action, they are the ones that stand out for their gamified engagement strategies. Trying to interpret this result, it may easily make sense as to why this occurs, considering these apps very explicitly aim to encourage daily behavioral changes, directly aligning with goals such as SDG 12 (Responsible Consumption and Production) and SDG 13 (Climate Action). As supported by the literature, gamification can provide a quicker convergence of habits omitting extensive explanations and triggering direct action [44]\u003c/p\u003e\u003cp\u003eIt is to say that the effectiveness of these apps heavily depends on individual motivation and external circumstances, and hence, despite their well-defined intended purpose to promote sustainable habits through interactive motivation systems, their performance can vary substantially [45]\u003c/p\u003e\u003cp\u003eMoving forward, apps that focus on Sustainable Consumption and Product Transparency, or Green Finance and Business Sustainability, generally use an informative approach instead. Two examples can be Good On You and Code Check, which function primarily as databases and scanners instead of interactive platforms. These applications provide extensive product details, ethical assessments, and financial recommendations which serve to educate users instead of providing entertainment. These apps are also in line with SDGs 8 and 12, which help to promote ethical consumption. This distinction emphasizes the importance of aligning an app’s interaction strategy with its intended outcome: while gamification is a useful tool for behavior change, information-driven apps are also, quite intuitively, expected to benefit more from clarity, credibility, and trust [46].\u003c/p\u003e\u003cp\u003eThe selected sustainability apps represent the extensive pool of digital developments in advocating for sustainability, yet numerous apps which are newer or niche, lack user reviews on the Google Play Store. The relatively high number of apps without user reviews (61.11%) may at first seem like a limitation, but the limited visibility does not necessarily reflect their quality or potential.\u003c/p\u003e\u003cp\u003eTherefore, these apps that are slowly expanding the market for digital sustainability promotion, each in their own unique way, have taken up the role of digital ambassadors of the SDGs, contributing to a variety of the goals they comprise, from raising awareness for quality education (SDG 4), to encouraging climate action (SDG 13), or supporting sustainable cities and communities (SDG 11) [47].\u003c/p\u003e\u003ch2\u003eB. Insights from Topic Modeling\u003c/h2\u003e\u003cp\u003eThe analysis of user reviews through topic modeling reveals detailed insights about how users understand and use mobile applications focused on sustainability. Sentiment analysis serves to capture the general emotional direction of the user feedback, whereas topic modeling serves to unfold the particular discussion topics including concerns, characteristics, and expectations that users have mentioned in their feedback. The five identified topics reveal distinct user experience perspectives. The following interpretations analyze these themes to reveal design strategies which work and those which do not in this domain.\u003c/p\u003e\u003cp\u003e● Interpretation of Topic 1: Engagement, Enjoyment, and Brand Enthusiasm. Topic 1 indicates that respondents prefer emotionally appealing, effectively designed applications (gamified or informative in nature). The design perspective of this topic demonstrates how emotional engagement and ease of use should be a careful consideration of designers as they need to create user experiences that are not only functional, but also rewarding and enjoyable.\u003c/p\u003e\u003cp\u003e● Interpretation of Topic 2: Technical Frustrations and Usability Concerns . Topic 2 indicates that one cannot simply have ethical intent without technical reliability. Developers should note that trust can erode quickly when technical issues go unresolved or when expectations set in the app description are not delivered in practice.\u003c/p\u003e\u003cp\u003e● Interpretation of Topic 3: Environmental Impact and Climate-Oriented Behavior Change. Consumers prefer applications that cause actions to be directly tied to climate impact [48].\u003c/p\u003e\u003cp\u003e● Interpretation of Topic 4: Food and Product Transparency. Food and product apps must provide correct product information and fast responses [49].\u003c/p\u003e\u003cp\u003e● Interpretation of Topic 5: Ethical Search, Pricing, and Eco-Friendly Shopping. \u0026nbsp;The 5th topic indicates the need in cost-conscious functionality that sustains ethical consumption behavior.\u003c/p\u003e\u003cp\u003eThe five topics together provide an extensive view of the repeated themes and user preferences within the sustainability app ecosystem. Users seek emotional engagement alongside ethical clarity, technical reliability, and real-world usefulness in their sustainability apps.\u003c/p\u003e\u003ch2\u003eC. Design Guidelines Informed by User Feedback and App Patterns\u003c/h2\u003e\u003cp\u003eThe research findings present an analytical summary of mobile applications related to sustainability, but the purpose of this study extends beyond this achievement. Practical design recommendations for designers who want to build effective, ethical user-centered digital applications can be derived.\u0026nbsp;\u003c/p\u003e\u003cp\u003eGamification needs to be thoughtful. The user interaction analysis revealed that apps use two different methods to engage users by either providing only information or using gamified elements. However, as it was discussed in the literature review and confirmed by user reviews, gamification does not automatically lead to success, and as a persuasive tool, it risks falling into manipulation, potentially creating an inauthentic connection with users and raising ethical concerns [50]. The topic modeling results showed that users like interactive features (Topic 1) but user interaction needs to be based on purposeful grounds and aligned with the sustainability goals of the app [51].\u003c/p\u003e\u003cp\u003eApp reliability depends not only on ethical design, but also functionality. Ethical persuasion and technical stability are needed to bring about behavior change. A poorly functioning app, no matter how well-intentioned, will eventually fail in delivering its persuasive goals. Ethical persuasive design must thus be accompanied by a strong foundation of usability, stability, and accessibility.\u003c/p\u003e\u003cp\u003eAutonomy and transparency must be part of persuasive strategies. In the literature about persuasive technology it was emphasized how there is an emerging concern about the ability to differentiate between influence and manipulation [52]. Users expect clear disclosure about the methods and reasons behind behavioral influence through strategies such as nudging, gamification, and social comparison. The need for transparency, apart from being strongly supported by the literature, is also indirectly reflected through user feedback as observed in the topic modeling results that emerged in Topic 2.\u0026nbsp;\u003c/p\u003e\u003cp\u003eUsers respond positively to concrete climate-related impact. The third Topic generated from topic modeling demonstrated how users value actionable assistance for environmental behavior. From carbon tracking to supporting reforestation or food waste reduction efforts, users tend to value more the applications that integrate straightforward metrics for indicating the impact that they are having to achieve the improvements they strive for in protecting the environment. Designers should create features that convert general sustainability targets into concrete, measurable activities that motivate users while providing a clear understanding of how their actions actually benefit the environment.\u003c/p\u003e\u003cp\u003eInformational value is a driving force in consumption-related apps. As observed through Topic 4 of topic modeling, users frequently interact with apps that allow scanning, rating, and comparing food and consumer products. Developers in this space of the sustainability apps landscape should focus on achieving database accuracy, transparency or ratings, and user interface elements that help them make informed choices in real-time shopping environments.\u0026nbsp;\u003c/p\u003e\u003cp\u003eAccessibility and cost sensitivity must not be ignored. For this guideline, the existing literature does not directly address it, however the reason for including it is based on the fifth Topic 5 emerging from the topic modeling analysis, where users expressed concerns about affordability, and ethical shopping decisions. Applications must provide affordable solutions to sustainability actions to onboard lower-income users.\u0026nbsp;\u003c/p\u003e\u003cp\u003eSustained user engagement should be encouraged. Widespread involvement requires dynamic problems, responsive feedback and rewards that address sustainability aims. As discussed in the literature, short-term behavior shifts are common, but long-term transformation is rare unless continuously supported by the app’s design. Designers should consider incorporating adaptive feedback, evolving challenges, streak tracking, and meaningful rewards to foster prolonged interaction, while still aligning with sustainability goals. Designers should involve diverse users in participatory design processes and adopt culturally sensitive approaches that respect different values, behaviors, and environmental challenges.\u003c/p\u003e\u003cp\u003eThe design guidelines presented at the end are one of the most important outcomes of this research. These suggestions are based on actual user feedback and app performance patterns observed in this study. They demonstrate that while certain elements, such as gamification or impact tracking, can be effective, their success really depends on how well they are implemented.\u003c/p\u003e"},{"header":"VII. Conclusion","content":"\u003cp\u003eThis thesis investigated the evolving relationship between mobile technologies with environmental sustainability through an analysis of 54 sustainability-focused mobile applications listed on the Google Play Store. The research evaluated sustainability app design while assessing their effectiveness through both design and user experience perspectives. Through a layered methodology that combined app categorization, sentiment analysis, and topic modeling of user reviews, the research sought to understand how these apps engage users, how they are perceived once in use, and how they succeed (or not) in supporting long-term behavior change toward environmental goals.\u003c/p\u003e\n\u003cp\u003eThe research findings demonstrate that the landscape for mobile sustainability applications may be rich in variety, but quality-wise it remains inconsistent. Numerous apps are populating the market for digital sustainability advocacy, indicating rising innovation and user engagement in this sphere. However, their effectiveness and ethical standards differ substantially.\u003c/p\u003e\n\u003cp\u003eThe design guidelines produced from this study integrate these findings into a practical framework that designers and developers can use to create more effective and ethically sound sustainability applications. App designers should focus on building systems that establish trust while respecting user autonomy as primary goals, to succeed in providing genuine support for sustainable behavior adoption instead of concentrating solely on engagement metrics and visual design. The provided insights work to transform sustainability app design discussions from basic engagement metrics to focus on creating substantial environmental impact through measurable and enduring results.\u003c/p\u003e\n\u003cp\u003eThis study provides a paradigm of mixed methodology that leans on user-centered design and NLP-based analysis by combining app categorization, sentiment analysis, and topic modeling to create a scalable mixed-method approach for evaluating sustainability apps that integrates system-level design perspectives with user-generated feedback.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSustainability apps are becoming very influential but have to strike a balance between innovation, ethics and transparency; however, their success depends on the design choices designers make and their willingness to create apps with purposeful design and user empowerment, as these are crucial foundations based on the existing literature. The findings show that apps need to be both innovative and engaging while maintaining transparency, inclusivity, and using ethical persuasive methods to build a more sustainable future. Future research must include cultural variations, long-term user loyalty, and co-design procedures in scarcely supported areas.\u003c/p\u003e"},{"header":"DECLARATION","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e There was no funding\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial Number:\u003c/strong\u003e not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish declaration:\u003c/strong\u003e not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate declaration:\u003c/strong\u003e not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics declaration:\u0026nbsp;\u003c/strong\u003enot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest:\u003c/strong\u003e There was no conflict of interest\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIX. Author contribution \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEC:\u003c/strong\u003e The project was conceptualized and designed, data was gathered and analysed, and the author prepared the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEC:\u003c/strong\u003e The individual provided assistance in the collection and analysis of data, made contributions to the interpretation of the results, and conducted a critical review of the paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEZ:\u003c/strong\u003e The individual offered assistance in the development of the research methodology and the interpretation of the collected data. Additionally, critically evaluated and revised the work to enhance its intellectual substance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEZ:\u003c/strong\u003e Participated in data collection, reviewed the literature, and contributed to the manuscript\u0026apos;s writing and editing.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAll data generated or analysed during this study are included in this published article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFoong Li Law, Zarinah Mohd Kasirun, and Chun Kiat Gan. Gamification towards sustainable mobile application. In 5th Malaysian Conference in Software Engineering (MySEC), pages 349\u0026ndash; 353, Malaysia, 2011. IEEE. ISBN 978-1-4577-1531-0. doi: 10.1109/MySEC.2011.6140696.\u003c/li\u003e\n\u003cli\u003eRory Mulcahy, Rebekah Russell-Bennett, and Dawn Iacobucci. Designing gamified apps for sustainable consumption: A field study. 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Current Opinion in Psychology, 42:89\u0026ndash;94, 2021. doi: 10.1016/j.copsyc.2021.04.008.\u003c/li\u003e\n\u003cli\u003eGeorgina M. Guill\u0026eacute;n, Daniel Fern\u0026aacute;ndez Galeote, Nevena Sicevic, Juho Hamari, and Jaco Quist. Gamified apps for sustainable consumption: A systematic review. In Proceedings of the 6th International GamiFIN Conference (GamiFIN 2022), volume 3147 of CEUR Workshop Proceedings, pages 135\u0026ndash;145. CEUR-WS.org, 2022. URL https://ceur-ws.org/Vol-3147/paper14.pdf.\u003c/li\u003e\n\u003cli\u003eTom Hunger, Marlen Arnold, and Rico Pestinger. Risks and requirements in sustainable app development\u0026mdash;a review. Sustainability, 15(8):7018, 2023. doi: 10.3390/su15087018.\u003c/li\u003e\n\u003cli\u003eBenjamin D. Douglas and Markus Brauer. Gamification to prevent climate change: A review of games and apps for sustainability. 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The 17 sustainable development goals. https://sdgs.un.org/goals, 2025.\u003c/li\u003e\n\u003cli\u003eBenjamin Brauer, Carolin Ebermann, Bj\u0026ouml;rn Hildebrandt, Gerrit Reman\u0026eacute;, and Lutz M. Kolbe. Green by app: The contribution of mobile applications to environmental sustainability. In Proceedings of the Pacific Asia Conference on Information Systems (PACIS 2016), page Paper 220. AIS Electronic Library (AISeL), 2016. URL http://aisel.aisnet.org/pacis2016/\u003c/li\u003e\n\u003cli\u003eGeorgina M. Guill\u0026eacute;n, Daniel Fern\u0026aacute;ndez Galeote, Nevena Sicevic, Juho Hamari, and Jaco Quist. Gamified apps for sustainable consumption: A systematic review. In Proceedings of the 6th International GamiFIN Conference (GamiFIN 2022), volume 3147 of CEUR Workshop Proceedings, pages 135\u0026ndash;145. CEUR-WS.org, 2022. URL https://ceur-ws.org/Vol-3147/ paper14.pdf.\u003c/li\u003e\n\u003cli\u003eRory Mulcahy, Rebekah Russell-Bennett, and Dawn Iacobucci. Designing gamified apps for sustainable consumption: A field study. Journal of Business Research, 106(5), 2018. doi: 10. 1016/j.jbusres.2018.10.026. URL https://www.sciencedirect.com/science/article/ abs/pii/S0148296318305071\u003c/li\u003e\n\u003cli\u003eBenjamin D. Douglas and Markus Brauer. Gamification to prevent climate change: A review of games and apps for sustainability. Current Opinion in Psychology, 42:89\u0026ndash;94, 2021. doi: 10.1016/j.copsyc.2021.04.008.\u003c/li\u003e\n\u003cli\u003eIfeoma Adaji, Peter Idoko, and Mikhail Ola Adisa. Insights from the review of apps that influence environmental sustainability. In Proceedings of the 32nd Conference on User Modeling, Adaptation and Personalization (UMAP \u0026rsquo;24), pages 154\u0026ndash;159. ACM, 2024. doi: 10.1145/3631700. 3664878. URL https://doi.org/10.1145/3631700.3664878.\u003c/li\u003e\n\u003cli\u003eWeng Marc Lim, Manish Das, Wamika Sharma, Aastha Verma, and Rajeev Kumra. Gamification for sustainable consumption: A state-of-the-art overview and future agenda. Business Strategy and the Environment, 34(1):1510\u0026ndash;1549, 2025. doi: 10.1002/bse.4021. URL https://doi. org/10.1002/bse.4021. Adjust. The ultimate gamification guide, 2023. URL https://www.adjust.com/resources/ guides/app-gamification/.\u003c/li\u003e\n\u003cli\u003eAdjust. The ultimate gamification guide, 2023. URL https://www.adjust.com/resources/ guides/app-gamification/. \u003c/li\u003e\n\u003cli\u003eRaymond Kight and Sandra Burri Gram-Hansen. Do ethics matter in persuasive technology? In Harri Oinas-Kukkonen, Khin Than Win, Evangelos Karapanos, Pasi Karppinen, and Eleni Kyza, editors, Persuasive Technology: Development of Persuasive and Behavior Change Support Systems, volume 11433 of Lecture Notes in Computer Science, pages 144\u0026ndash;155. Springer, Cham, 2019. doi: 10.1007/978-3-030-17287-9_12. URL https://doi.org/10.1007/978-3-030-17287-9_12. \u003c/li\u003e\n\u003cli\u003eDennis Benner, Sofia Sch\u0026ouml;bel, and Andreas Janson. It is only for your own good, or is it? Ethical considerations for designing ethically conscious persuasive information systems. In Proceedings of the Twenty-Seventh Americas Conference on Information Systems (AMCIS 2021). Association for Information Systems, 2021. URL https://www.researchgate.net/publication/355425443_It_is_only_for_your_own_good_or_is_it_Ethical_Considerations_for_Designing_Ethically_Conscious_Persuasive_Information_Systems. \u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTABLE I. Sustainability App Thematic Categories, Descriptions, and SDG Alignment\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"348\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCategory\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eShort Description\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRelevant SDGs\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eEnvironmental Awareness and Education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eRaises awareness and educates through news, games, or missions.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 4 (Quality Education), SDG 13 (Climate Action)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eCarbon Footprint Tracking and Climate Action\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eHelps track, reduce, or offset carbon emissions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 13 (Climate Action), SDG 12 (Responsible Consumption)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eSustainable Consumption and Product Transparency\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eGuides ethical choices with brand ratings and certifications.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 12 (Responsible Consumption), SDG 8 (Decent Work and Economic Growth)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eSustainable Lifestyle and Habit Building\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eEncourages eco-friendly habits via tips and challenges\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 12 (Responsible Consumption), SDG 3 (Good Health and Well-being)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eSustainable Mobility and Transport\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003ePromotes low-carbon travel with gamified incentives\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 11 (Sustainable Cities), SDG 13 (Climate Action)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eFood Sustainability and Waste Reduction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eSupports sustainable eating and food waste reduction.\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 2 (Zero Hunger), SDG 12 (Responsible Consumption), SDG 13 (Clima Action)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eCircular Economy and Recycling\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eMotivates recycling and reuse through rewards and education.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 12 (Responsible Consumption), SDG 9 (Industry, Innovation and\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eGreen Finance and Business Sustainability\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eFocuses on ethical investing and green business strategies.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 9 (Industry and Innovation), SDG 8 (Decent Work), SDG 13 (Climate Action)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 102px;\"\u003e\n \u003cp\u003eCommunity Engagement and Social Platforms\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eBuilds communities around shared environmental action.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSDG 17 (Partnerships), SDG 11 (Sustainable Cities), SDG 13 (Climate Action)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTABLE II. Categorization of Sustainability Apps\u003c/p\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"343\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eApp Name\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGamified\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eInformative\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 53px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eReviews\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eThematic Focus\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGreen the Planet / 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eEnvironmental Awareness and Education (4, 13)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eEarth Hero: Climate Change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eEnvironmental Awareness and Education (4, 13)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGo Green Challenge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eSustainable Lifestyle and Habit Building (12, 3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGreen Point: Food \u0026amp; Cosmetics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eNo\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eCircular Economy and Recycling (12, 9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eMy Green City\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eNo\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eNo\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eEnvironmental Awareness and Education (4, 13)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGreen Money\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eNo\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eGreen Finance and Business Sustainability (9, 8, 13)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGanddee\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eNo\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eCommunity Engagement and Social Platforms (17, 11, 13)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eEarth5R\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003eYes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eSustainable Consumption and Product Transparency (12, 8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eContinues\u0026hellip;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003cp\u003eTABLE III. Overview of App Distribution by User Interaction Type, Review Availability, and Thematic Focus\u003c/p\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"326\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUser Interaction Type\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eApp Count\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePercentage (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003eGamified\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eInformative\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eBoth gamified and informative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e12.96%\u003c/p\u003e\n \u003cp\u003e31.48%\u003c/p\u003e\n \u003cp\u003e55.56%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (User Interaction Type)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e54\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e100%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eApp Review Availability\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eApp Count\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePercentage (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003eApps with reviews\u003c/p\u003e\n \u003cp\u003eApps with no reviews\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e38.89%\u003c/p\u003e\n \u003cp\u003e61.11%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (User Interaction Type)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e54\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e100%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eThematic Focus\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eApp Count\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePercentage (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003eEnvironmental Awareness and Education \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eCarbon Footprint Tracking and Climate Action \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSustainable Consumption and Product Transparency\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;Sustainable Lifestyle and Habit Building \u0026nbsp;Sustainable\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMobility and Transport \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eFood Sustainability and Waste Reduction \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eCircular Economy and Recycling\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eGreen Finance and Business Sustainability\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eCommunity Engagement and Social Platforms \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e20.37%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e24.07%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e18.52%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e14.81%\u003c/p\u003e\n \u003cp\u003e3.70%\u003c/p\u003e\n \u003cp\u003e\\\u003c/p\u003e\n \u003cp\u003e7.41%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e9.26%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3.70%\u003c/p\u003e\n \u003cp\u003e9.26%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (User Interaction Type)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e54\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e100%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Mobile Applications, Sustainability, User Interaction Strategy, LDA Modeling","lastPublishedDoi":"10.21203/rs.3.rs-7310678/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7310678/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis paper explores the role of mobile applications in promoting sustainable behaviors and environmental awareness. The researchers study the related issues of the impact of sustainability-oriented app design on user engagement and motivation. Using a mixed-methods exploratory approach, the researcher analyzed 54 mobile applications from the Google Play Store, categorized by interaction type (informative, gamified, or both), environmental theme (e.g., ethical consumption, carbon tracking), and user review availability. Of these, 21 apps with user feedback were further analyzed using Natural Language Processing techniques. The VADER sentiment analysis was used to determine user satisfaction and the topic modelling analyzed using the LDA topic modelling to identify common themes. The findings highlight that app success relies not just on informative content or basic gamification, but on clear, motivational content that links sustainability goals to practical daily actions. Users value straightforward interfaces, consistent performance, and ethical accessibility. More importantly, the research defines three frequently neglected yet fundamental aspects of mainstream app design: inclusivity, affordability, and transparency. The thesis underlines that these aspects have a serious influence on the trust of the user community and a long-term involvement. The study provides a user-based recommendation on design solutions that developers can use to develop ethical, user and context-sensitive sustainability applications. In general, the thesis can be useful in the domain of digital sustainability, creating bridges between the principles of design and user expectations to improve the role of mobile technology in achieving sustainable behaviors.\u003c/p\u003e","manuscriptTitle":"Design Insights from Sustainability Apps to Guide User Centered Mobile Application Development","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-02 07:45:01","doi":"10.21203/rs.3.rs-7310678/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1fb09385-2457-49f2-bbd7-3591ae924fb0","owner":[],"postedDate":"September 2nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-14T13:10:06+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-02 07:45:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7310678","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7310678","identity":"rs-7310678","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}