Integrated Digital Nudge in Gamification for Public Transportation Applications

Abstract

A shift from private to mass transportation is one of the main goals of many governments. In this context, integrating digital nudges into gamification on digital platforms is a promising approach to influencing and changing user behavior. This study emphasizes the importance of understanding user needs and design requirements in developing effective solutions. A mixed-methods approach combined user interviews, expert interviews, thematic analysis, HEXAD questionnaires, and gamification workshops to collect and analyze needs. These methods comprehensively understand user expectations, gamification elements, and appropriate digital nudges. Based on these findings, a prototype was developed, which was then evaluated through a preliminary evaluation in the form of usability testing using questionnaires and interviews. The study results indicate that the design of digital nudges in the context of gamification can be effectively applied to public transportation applications and can potentially change user behavior in a more positive direction.

1. Introduction

A user interface aims to maximize usability and user experience when using information systems. User experience occurs due to an internal process in the user, so there are needs, motivations, expectations, and feelings [1]. Research in the field of HCI (human–computer interaction) has also studied the influence of an interface on changing user behavior. One type of interface is called the persuasive system. B. J. Fogg proposed the Fogg behavioral theory (Fogg behavioral model). According to Fogg, persuasive technology is an interactive computing system designed to change people’s attitudes or behavior [2,3].

Gamification is also said to be a form of persuasive system, with game elements designed to motivate users [4]. The gamification method applies elements found in games to non-game applications to provide a better experience and increase user engagement [5,6].

Gamification has been used in various fields. According to a literature study conducted by [7], 50% of gamification studies are in education, followed by health. However, there is still little gamification in transportation and mobility. However, some countries have implemented gamification in transportation, such as Australia, the UK, the Netherlands, Sweden, and New Zealand [8].

A solution to encourage the transition from private to public transportation is to integrate services into a multimodal network that encourages interchange between different modes of transportation; this is called mobility as a service (MaaS). Research in this field is still mainly centered in North America, Europe, and Australia. In Asia, it is represented by China and India [9]. In general, this research will be significant because it takes an object in the capital city of Indonesia, a developing country in Asia that is included in the G20; Jakarta is a metropolitan city that is included in the list of the most congested cities.

In addition to gamification, in recent years, researchers have also come up with what is referred to as digital nudging. In today’s digital world, users will often interact with interfaces. The design of an interface will affect the choices and decisions that users will make. The user will make choices based on the choice architecture presented in the user interface/system interface [10,11,12]. Humans have cognitive limitations that can affect how users make decisions. Several psychological effects can influence humans in making decisions, both consciously and unconsciously [1]. These things allow a system designer to manipulate it so that it is possible to direct users into making decisions based on the choices available. This principle is referred to as a “nudge”, which means that people’s choices are manipulated by how they are presented [13]. Moreover, in an increasingly complex world, people are presented with various choices.

The integration of nudges and gamification demonstrates the potential of persuasive technology to effectuate substantial behavioral change [14]. This combination indicates that a multi-strategy approach may be more efficacious than depending on a single technique. Moreover, implementing gamification and digital nudges necessitates considering the context and individual user objectives. The design of a gamification system aimed at promoting cybersecurity [15] will differ from that of a gamification platform intended to encourage sustainable transportation [16]. The outcomes of integrating gamification with digital nudges exhibit varied effects. Experimental and quantitative evaluations have revealed varying benefits of multiple gamification and nudge tactics implemented in studies. The research by Lieberoth [14] shows that integrating nudges with gamification produced a more significant impact than gamification in isolation. Similarly, the implications of nudges and gamification on e-learning are only observed under conditions of more engaged learners. Similarly, gamification and digital nudges in transportation application features only impact users with specific habits [17]. The research undertaken by Petrykina, Schwartz-Chassidim, and Toch [15] indicates that the impacts of gamification and nudging manifest under particular settings. Some tactics, such as gamification, are more effective than others, including nudging [18]. Based on the research, several gaps emerged, including that the research only combined nudge and gamification elements into the application. Further, the research was conducted in European countries. As stated by Zimmermann, gamification research on transportation would be better if conducted in countries other than Germany and in cities in Europe [17].

Nudges have been applied in many countries, and the results show that the implementation of nudges in Denmark, Germany, and South Korea shows stable acceptance, while in the United States, the results are somewhere in between. The acceptance of nudges will also be stable if government intervention exists, especially in authoritarian countries like China [19]. Indonesia is the 3rd largest democracy in the world after India and the United States. One of Indonesia’s more successful nudges is encouraging people to pay taxes [20]. Therefore, applying nudges to other sectors, such as transport in Indonesia, would be interesting.

This study addresses the gap in the literature by integrating nudge theory into gamification to optimize the reach of strategies that influence user behavior on digital platforms. Specifically, this study addresses the limited exploration of how digital nudges can be systematically embedded into gamification elements. This study, conducted in Jakarta, a major metropolitan city in Indonesia, provides contextual insights into the use of gamification and digital nudges in public transportation systems in developing countries. The study contributes theory to the design of gamification and digital nudges, especially in urban mobility. Furthermore, this study introduces a novel methodological framework for designing and implementing an integrated digital nudge and gamification approach, which offers a foundation for future research and applications in similar socio-technical settings.

The objective of this study is to identify the user requirements necessary for the design of gamification and digital nudges for public transportation applications.

To this end, the following research questions will be addressed:

(1)

What are the user and design requirements needed in designing gamification and digital nudges for public transportation applications?

(2)

What are the preliminary evaluation results of gamification and digital nudge in public transportation application?

2. Literature Review

2.1. Gamification

Gamification is the application of game elements to a non-game system [21]. The game in a computer application is a focus of research in HCI [22,23]. Gamification research has also contributed to science in the field of human–computer interaction (HCI) [24].

Gamification, which is an extension of game research, has also caught the attention of researchers in HCI. In some publications, gamification is said to be part of the HCI scientific field [25,26,27]. Research on gamification topics has also been published in the HCI journal and forms a part of the Association of Computing Machinery Conference on Human Factors in Computing Systems, considered to be one of the most prestigious conferences in the field of human-computer interaction (HCI) [28,29,30,31].

Gamification also describes a system that aims to motivate users intrinsically. Game elements in gamification are intended to emulate game effects on users, making them feel engaged and bound in a game without coercion [32]. Where there is gamification in HCI research, the extent to which HCI is associated with the human factor is termed usability. But as technological advances develop between computers and humans, in addition to the concept of usability, issues develop, which include creating a system or application that is esthetically interesting and emotionally engaging [33], as well as developing a system that can engage (engage) and motivate users to continue using it [34]. Gamification is a design approach that uses gaming/game elements in various systems and services to provide a fun experience [7].

A common theoretical framework for understanding the potential motivations for gamification is the self-determination theory (SDT) [7,35]. This theory, which considers human motivation intrinsic or extrinsic, depends on whether an activity is conducted for the sake of the activity or for reasons outside of it. For an intrinsically motivated behavior, it is most likely that behavior results from three motivational needs: (1) competence, the feeling of being capable; autonomy/, the feeling that those actions are self-originating and voluntary; and associations/relatedness, mutual concern, values, and a sense of togetherness concerning other social figures and groups [36,37]. Although human resource theory is derived from the psychology family that analyzes how people are motivated to do things, the HCI research field also extends to human resources. In one literature study, 110 research articles were published on CHI and CHI PLAY [38].

Based on the SDT, gamification consists of three main elements related to the affordances of intrinsic motivation [39]. Affordances refer to the various elements and mechanisms that make up gameplay/games and support triggering the experience of playing in a system. Psychological impact refers to psychological experiences such as competence, autonomy, and relatedness, or, for example, enjoyment and engagement, which are usually induced by games and gamification. Affordance is a concept known in HCI and interactive design, introduced to the HCI family by Don Norman [40].

Gamification research provides scientific contributions, including the application design of gamification using UCD. A challenge faced in gamification design is determining game elements that are appropriate for a system. Several aspects can be used to determine game elements, including demographic, cognitive, behavioral, anthropometric, and attitude perspectives [24,41,42]. The use of UCD in gamification design has similar motivations to other systems, with users and stakeholders participating in all processes, from design to evaluation [43].

UCD methods include interview design, brainstorming, user stories, persona-making, and prototyping. Meanwhile, usability testing, user interviews, expert interviews, questionnaires, and experiments have been used for design evaluation [43,44,45]. For example, think-aloud methods ensure that the gamification elements (progress tracking) can motivate users. This can lead to successful learning in e-learning applications [46].

Research on gamification in information systems has been applied in various sectors, such as education, health, marketing, crowdsourcing, productivity, and transportation. Much of the research focuses on how gamification affects user behavior changes in the application. The purpose of applying this gamification varies, with some results being seen from the psychological side, which then affects the user’s behavior. A study of the literature by Koivisto summarizes some of the psychological effects posed by applying gamification, including affective, cognitive, social, attitude, and motivation impacts [7]. For example, the application of gamification to e-commerce can make consumers more loyal, make students or students better at taking exams [47], cause users of crowdsourcing applications to contribute more [48], and allow health application users to do more exercise [49]. In the field of environmental research, several factors contribute to gamification, such as encouraging people to choose a more sustainable mode of transportation [50].

Transportation research examines the factors that can influence the intention to continue using a service; based on research from [51] and Javadinasr [52], the enjoyment and pleasure factors constitute an influencing factor. The application of gamification and the factors behind it are also loaded with factors related to hedonics [49], enjoyment [53], fun [54], and pleasure. So, gamification is relevant when applied to public transportation applications. Based on the literature studies, the authors found that some gamification elements have been used in transportation applications. The most commonly applied elements are points, followed by other elements, such as monetary incentives, badges, ranks, challenges, competitions, leaderboards, collaboration, goal setting, social networks/social interaction, progressions, prizes, levels, narratives, quests, coins, and achievements [55].

2.2. Digital Nudge Theory

A digital nudge is an element or feature used in a choice architecture. A user interface designed to direct user choice and manipulate user decision making is the goal of a choice architecture [56]. An employee in HCI research could be considered a choice architect, as users of information systems and interactive systems such as e-commerce sites always make small choices and big decisions [57]. Therefore, digital nudge research can constitute part of the HCI scientific domain because user interface design is part of the HCI field [58]. Research on digital nudges has also been published in many HCI publications [59].

The study of digital nudges typically investigates the effects of nudge elements applied to an information system, such as sites and mobile apps. A nudge is categorized as a characteristic of a user interface element. [59,60,61]. The nudge mechanism on an interface relates to decision-making processes. Psychological research suggests that individual decision-making is associated with certain cognitive processes [62]. For an intervention to be considered a nudge, an intervention must not impose significant material incentives [63]. This is how a digital nudge affects individual decision making at various information processing stages. In general, individuals avoid psychological and physical efforts when decision making. On the one hand, psychological effort implies that certain choices are cognitively demanding and time consuming. As a result, individuals prioritize decisions that require less exertion than options that require relatively more effort [64]. Digital nudges lower cognitive and physical effort demands when making choices by providing simple, relevant information and reducing steps [60]. The development of HCI science is derived from cognitive science; it is also the basis for the development of the UCD principle (user-centered design), which promotes human beings as a system [65].

Some digital nudge studies relate to the effect of applying a nudge to an interface, such as research using an experimental design as its research method. Researchers usually apply two different kinds of design to an interface and then see which design has more effect or achieves better goals. Therefore, it is helpful to understand the application of digital nudges to other domains of problems, such as cyber security transportation [66], e-commerce [58,67], enterprise resources planning applications [68,69], social media [70], sustainability [71,72], and health [73,74].

Initially, two studies attempted to identify the elements of a digital nudge, i.e., the research of [1]. The approach they described is similar, illustrating the psychological effects of the nudge and how it can be applied in the context of the digital environment.

Research on nudges applied to the digital environment has attempted to demonstrate some nudge elements and mechanisms in electronically based systems, such as in WebApp applications and other technologies. A study undertaken by Mirsch [75] described twelve types of nudge elements that can be applied to a digital system. Recent research by Caraban [76] outlines 23 nudge mechanisms implemented in a digital system. They are grouped into six categories: facilitate, confront, deceive, social influence, fear, and reinforce [76].

2.3. User-Centered Design

According to [77], UCD is seen as a discipline, practice, field, craft, framework, philosophy, or way of creating tools that incorporate people into the design process. When using UCD techniques, designers create user profiles, defining their preferences and behaviors for different parts of a particular application, and then use these data to influence design choices. The ISO (ISO 9241-210, 2010) standard offers six essential guidelines to guarantee a successful user-centered design project [78]. These are as follows:

• The design is based upon an explicit understanding of users, tasks, and environments.
• Users are involved throughout the design and development.
• The design is driven and refined by user-centered evaluation.
• The process is iterative.
• The design addresses the whole user experience
• The design team includes multidisciplinary skills and perspectives.

3. Materials and Methods

At this stage, individual interviews with transport users were conducted. The selected interview respondents encompassed many demographics, including different age ranges and generations, genders, and occupations. These interviews aimed to gain user feedback and experiences related to their utilization of public transportation. The interviewers started probing by asking for impressions and images of public transport. Then, users were asked for their opinions on public transport’s good and bad aspects. Users were also asked for their opinions and suggestions on improving the quality of public transport. The outcomes of these interviews were evaluated to obtain user requirements for creating the gamification and digital nudging models. Due to the ongoing pandemic, the interviews were conducted online using a video conferencing platform.

The interviews were used as data collecting methods to determine the user requirements. Such an approach was adopted from these papers [79,80,81]. In collecting user requirements, this research interviewed nine public transportation users. Interviews were conducted in the period of March–July 2023. The interviews were conducted online using Google Meet. The interview data collection protocol was conducted in several stages, following the procedure [82]. The procedure for conducting interviews was as follows:

• As this research employs a structured interview format, preparing the interview questions in advance was essential.
• We determined potential respondents as regular and non-regular users of public transportation, with demographics of age above 18 years, male and female.
• Searched for respondents by contacting colleagues and through WhatsApp Groups for respondents with related criteria.
• After the respondents were determined, they were contacted by the research assistant team and then made an appointment online.
• Interviews were conducted online using a video conference application. All the interviews were audio-recorded
• The results of the interview were then transcribed. The duration of interviews was between 15 to 20 min

The interview technique was conducted by deriving the questions from the research question. The questions in this study are as follows:

• How do passengers perceive public transportation?
• What is the quality of the passenger experience while using public transportation?
• Does the passenger base possess knowledge regarding environmental concerns and their correlation with the utilization of public transportation?
• What are the preferred and disliked features of public transportation apps?

3.1. Participants

The respondents for this interview comprised nine people from different backgrounds. Participant recruitment was accomplished using purposeful sampling, and data collection was performed with in-depth, structured interviews. These interviews were recorded, transcribed, organized, and analyzed using systematic, qualitative thematic analysis. This study utilizes open data from Mendeley Data titled Observation and passenger interview of public transportation in Jakarta, which includes photographs and interview transcripts collected between 2024 and 2025 [83].

Table 1. Respondent demographic.

Respondents	Age	Gender	Occupation
R1	20	Male	Worker
R2	35	Female	Worker
R3	20	Female	Students
R4	28	Female	Worker
R5	29	Female	Worker
R6	20	Male	Students
R7	40	Male	Worker
R8	20	Male	Worker
R9	43	Male	Worker

shows information about the demographics of respondents who use public transportation.

The study also interviewed four transport experts from the regional government, the Ministry of Transport, and public transport operators. This interview was conducted in November 2024–January 2025.

Table 2. Respondents from experts.

Respondents	Institution
R1	Ministry of Transport
R2	regional government
R3	Transport operator
R4	Transport operator

shows information about the expert respondents. The results of the themes are based on interviews with community respondents and verified by expert sources.

3.2. Thematic Analysis Method

Thematic analysis is a method for identifying, analyzing, and reporting patterns/themes in data. It minimally manages and describes data sets that are rich in detail [84]. It is also a form of pattern recognition in data, where emerging themes become categories for analysis [85].

Thematic analysis is used to see something that is not explicitly visible to others; a pattern or theme in seemingly random information can be observed. The perception of this pattern starts the process of thematic analysis. The next significant step is classifying or coding the pattern and labeling it, followed by the third major step in thematic analysis, which is interpreting the pattern.

A theme is a code found in the information that minimally describes and organizes possible relationships and maximally interprets aspects of the phenomenon. A theme can be identified at the manifest level (directly observable in the information) or at the latent level (underlying the phenomenon).

Themes can be generated inductively from raw information. Themes can also be generated deductively from theory and previous research; ‘theoretical’ thematic analysis is driven by the researcher’s theoretical or analytical interest in the area [86,87]. Another approach is hybrid methods, combining inductive and deductive methods based on pre-existing theories or codes [85].

After developing codes or identifying themes, this information can be used in various modes and methods of analysis. One analysis method uses Intensity scoring, which measures the strength, depth, or emphasis of a theme or code in the data [87].

The following are the stages of thematic analysis according to [86]:

• Familiarization with the data

Reread the data thoroughly so that the researcher understands the context and content.

b.

Generating initial coding

Mark essential parts of the data that are relevant to the research questions.

c.

Searching for themes

Clustering codes into potential themes that have greater meaning.

d.

Reviewing themes

Evaluating whether the themes are sufficiently strong, consistent, and representative of the data.

e.

Defining and naming themes

Giving each theme a name and a clear explanation.

f.

Writing the report

Composing a narrative based on the themes and discussing it, considering relevant theory or literature.

Thematic analysis methods are increasingly used in HCI (human–computer interaction) research, especially that related to health and well-being. One of the reasons for this is that in qualitative research, the emphasis is not on measuring numbers but on understanding the quality of specific technologies and how people use them in their lives, how they think about them, and how they feel about them [88,89]. In general, qualitative methods are used in HCI research, collecting user requirements, understanding the situations in which technology is used and might be used, and evaluating how technology is used in practice [90]. In addition, thematic analysis is also used during usability evaluations, such as in gamification applications [91] and e-health applications [92].

In this study, data saturation was examined by looking at the themes that frequently emerged from the first time the interview was conducted. Data saturation describes when no new information emerges from coding, and when no new properties, dimensions, conditions, actions/interactions, or consequences are seen in the data [93]. This qualitative study conducted in-depth interviews with nine participants. Although small, this sample allowed for a rich and detailed exploration of individual experiences. Data saturation is observed when themes re-emerge after following guidelines from the qualitative research literature. Our number of nine respondents in the sample for qualitative research appears sufficient to have reached data saturation in finding themes in this study [94,95]. Two people intensively read the transcription and confirmed which themes frequently appeared. Then, this was presented through a table showing the frequency of emerging themes.

3.3. HEXAD

The HEXAD gamification user types aim to systematically categorize users according to their level of responsiveness to different gamification strategies. The proposed approach introduces a typology for categorizing the users of gamified systems, allowing users to be grouped according to intrinsic and extrinsic motivating dimensions. The HEXAD model consists of six distinct gamification user categories: Socializers, Free Spirits, Achievers, Philanthropists, Players, and Disruptors [96].

HEXAD was utilized to customize gamification by identifying the game participants’ characteristics. The identification of each game player was anticipated to yield game elements tailored to the player’s specific attributes. Questionnaires were distributed in January–February 2023, with 113 respondents.

3.4. Gamification Workshop Method

In previous research, it was mentioned that gamification design can determine gamification elements by holding group discussions and brainstorming with participants. Our research results show that the gamification elements that usually appear are just that, surrounding points, badges, and leaderboards, as reported by other researchers following brainstorming in an interactive design class. A lecturer who teaches a course will give instructions to students, and then the students will work in groups to create ideas [97].

The authors argue that this approach will yield positive results if the individuals involved in the FGD or brainstorming processes comprehensively understand games and their underlying components. Building upon [98] previous research, which derived the concept of gamification aspects from the MPORG game, the authors performed a workshop to gather gamification elements that could be implemented. This workshop was held from January to October 2023. The researchers conducted a workshop three times with first-year university students as the participants. The student demographic ranged from 18 to 20 year olds with a passion for PC and mobile gaming.

The researcher performed the following procedure:

• Presented and explained gamification and its elements to respondents. Gamification elements were described based on gamification taxonomy from [99,100].
• Explained the functions and features of public transportation applications. The JKL application is a case study. The basis for choosing this application was that this application is the only application that offers integration between modes of public transportation at an affordable price.
• Using collaboration tools (MIRO), participants could provide input on gamification ideas.
• The researcher analyzed the data obtained by classifying it based on the ideas received on the application and features in general.

3.5. Digital Nudge Design

Digital nudge design has two types: digital nudge for application and digital nudge for gamification. Digital nudges are one of the novelties of this research, where the expert involvement of practitioners in the field of UX is employed to review the gamification application prototype and then provide suggestions regarding digital nudge.

Two methods were used to design digital nudges.

• Literature study: Determining nudges through literature studies. Researchers adjust between gamification elements and nudges that can be applied according to the objectives achieved; for example, default nudges can be used to direct users to certain choices in the application installation process where the “standard” radio button is already checked. Another default example is the discount option in e-commerce. By default, the developer chooses the most favorable discount or reward for the user. This default aims to make it easier for users to select an option because users do not need to think and calculate what rewards or discounts are more profitable.
• Expert judgment: asking for expert opinions in the UX field regarding gamification elements that can be given nudges. In this process, the researcher presents the gamification application to the expert, who then gives their ideas and opinions.

3.6. Usability Testing

This study used usability testing as an evaluation method. This test focused on the activities carried out by users when using and interacting with the product. Previously, the researchers created two versions of the system: application A and application B. Application A is a transportation application with gamification. In contrast, application B is a transportation application with gamification and a digital nudge.

The implementation procedure was carried out by selecting respondents. In this case, the researchers used convenience sampling. Respondent sampling was conducted in a campus environment, which consisted of workers and students. The selected respondents had to have previously used public transportation and transportation applications. The numbers of respondents chosen were 10 respondents for application A and 10 respondents for application B. According to Nielsen [101], five respondents are sufficient to find problems in usability testing. The two samples were independent, meaning respondents for applications A and B differed, as intended to prevent bias during the experiments

The researchers installed the application on a Samsung mobile phone prior to experiments so that there would be no technical obstacles when the application was installed on each respondent’s mobile phone. This study follows the evaluation design conducted in other gamification [102,103] and digital nudge [104,105] studies. The SUS questionnaire is a measuring tool used to measure usability. The questionnaire used was taken from the SUS and adapted into Indonesian [106]. The scenario given is as

Table 3. Usability testing scenario.

Task	Scenario
Searching for a route	You will depart from Blok M station to Ciledug. You open the JKL application and search for public transportation routes that you can use.
Choosing a route	You choose the route that you think is the fastest or cheapest.
Buying a ticket	After choosing, you will buy a ticket.
Checking in to a station/bus stop	You can check in using the existing ticket by scanning the QR code.
Checking points	After using the ticket, you want to check your earned points.
Viewing rewards	You also want to see the rewards that you can redeem.
Playing mini-games	You want to play mini-games on the loyalty program page.

below.

4. Results

This section will present the research findings, commencing with synthesized user requirements, gamification elements, and digital nudges. Subsequently, the preliminary evaluation is executed through usability testing.

4.1. User Requirements

4.1.1. Thematic Analysis

Based on the transcripts, the authors conducted the thematic analysis to synthesize the results of the interviews. In this case, the results of the interviews were analyzed manually using the Microsoft Excel application. The first process summarized the interview results so that each respondent’s essence was obtained.

Following the study in [79], the interview results were grouped according to similar categories. In this case, the categories displayed are related to the quality of public transportation. Then, this was also associated with the experiences and feelings of users when using the application.

Table 4. Thematic analysis of respondents.

No	Category	Frequent Themes	Example Quotes
1	Things liked about public transportation	Affordability	Affordable because I have to take the commuter line from home to the office daily.
		Punctuality	If from the commuter line, which is most often used to describe it, the good thing is that it is now quite on-time, which means that it is rarely late and practical
		Convenience	I like the cleanliness of the carriages, no matter how crowded they are.
		Accessibility	but now it’s so easy to integrate all transportation. For example, the KRL can be directly connected, too, so walking in front of the trans-Jakarta bus stop is easy. Transjakarta also connects to the MRT so we can quickly move from one place to another.
		Safety	There is also a women’s carriage, which is also supportive, so even though it is based on safety, there is also safety in terms of comfort.
		Payment	Busways are cold and cashless, and stations have been expanded and improved.
2	Things disliked about public transportation	Convenience	But the drawback is that it is full, like crowded.
		Punctuality	What needs to be improved is to be more punctual. Mostly, it’s just when I’m waiting. I sometimes wait for TJ for almost 20 min.
		Facility	I’m a bit confused because the exit 1 and 2 doors are confusing, and the instructions can be wrong if we don’t carefully look. The escalator is still lacking at the KAI, so if in Tanah Abang there are a lot of turns up. Down the stairs, it’s confusing if we want to bring small children there, if there can be more escalators and then there is a slightly sloping road if you want to bring a stroller or something like that, it should be better.
		Information	Time, because it is unreliable
		Information	Currently, the train line is unclear as far as I am and very crowded.
		Accessibility	Traveling up the stairs, I have much baggage, so climbing stairs is hard.
		Safety	Fear of losing things, especially carrying a laptop, right?
		Payment	In the past, the busway was not yet air-conditioned and cashless.
		Accessibility	For me, public transportation is still very minimal right now. It’s like public transportation that can’t deliver to the house, so we have to go to the main road unless we use Grab or Gojek, which have to pick us up at home, while for Grabcar, you have to pay much money.
3	Things liked about transportation apps	Route feature (3)	Navigation, yes. He can be like a navigator, so (as navigation)
		Time information	My favorite thing is to be able to see the departure schedule.
		Bus/train position	And where the train is positioned. Although it’s not real-time, it’s okay.
		Ticket buying	It is nice to top up from my phone so I don’t have to fill it up again or monitor busway route tracking. Suppose MRT is the most preferred ticket purchase. In that case, so many payment options are using the wallet; he has a choice of several e-wallets, and then if you use the application, for example, MRT, the balance does not need to be at least different from using an e-money card if the card must have a minimum balance.
		Sharing information	If I like “Travi”, when I’m waiting for idle time, I want to check that there is reporting so users like to post on this bus, for example, bus number 8. How come it’s not visible, then other passengers answer that he took bus number 8, the position is in Meruya again, there is a severe traffic jam, finally, the information does not only rely on GPS data but there is communication between people.
4	Things disliked about transportation apps	Inaccurate information	Google Maps likes to be given a road that is bad/annoying suddenly. Sometimes, we stray even though we are close (inaccurate navigation)
		Lack of features (real-time tracking)	Maybe it’s made so that the tracking can be more real-time
		Bad user experience (UX)	For the application on the commuter itself, maybe it’s more about the interface because the menu is only written in the form of an icon, so you have to read it. For example, if I want to see the schedule, which button is it? So I think it should be made in the menu like the current application, where there is an icon. So we already know we want to see departures see the clock icon, and then it’s also quite tricky for the search.

shows the results of the thematic analysis.

The thematic analysis results also calculated the number of times each theme appeared. This diagram explains how many themes appear, along with their sentiments. For example, most people like the mode of train transport because of its punctuality. However, this is not the case for the bus mode, where the arrival time remains unclear, as shown by the theme frequency in Figure 1 below.

Based on the results of the interviews with the users, several things can be said about the quality of public transportation services (QoS). These results were then confirmed and verified using expert sources. The following paragraphs explain the points raised by the experts.

• Affordable

Cheap and affordable were the most common things respondents said they liked and expected from public transport. “transport prices in Jakarta are currently the lowest compared to other Asian countries”.

2.

On time/not on time

Respondents also prefer on-time public transport modes. In this case, only the train mode can provide time certainty to passengers. Meanwhile, the bus mode is often perceived as unreliable regarding punctuality. Researchers suggest that passengers value time certainty, which can be addressed by enabling bus vehicle tracking. “Currently, the OTP (On-time performance) of buses is still around 80%, while trains are 90%. So there is still waiting time for buses”.

3.

Comfortable

This factor is characterized by the fleet’s air conditioning, cleanliness, and tidiness. “Rejuvenation of the fleet with air conditioning is performed annually”.

4.

Accessibility/transfer distance

This factor relates to the availability of stops, terminals, and routes close to residences and destinations. However, passengers do not like the transfer distance to be too far if they change stops or terminals. “Access to mass public transport is already 80% of Jakarta. But for greater Jakarta, it is still below 10%”.

5.

Safe

The provision of female carriage facilities characterizes security. Security guards are also available at bus stops and terminals. “there are already regulations governing safety standards with CCTV. Trains also provide special carriages for women, and buses provide a section for women”.

6.

Payment

Today’s young generation prefers cashless payments. Therefore, cashless payment modes are mandatory for transport providers to implement. “Most payments are made using e-money cards. In the future, we will implement ABT (account-based ticketing)”.

7.

Inaccurate information

The app and information boards are still confusing to respondents, with incorrect timetables or routes. “Exact and real-time journey information is only available in train mode”.

The findings also inform us of the selection of gamification elements to deliver the quality of public transport users desire. For instance, the interview results show that users prefer affordable public transport, which can be supported through gamification elements that create a perception of affordability or offer monetary benefits, such as points that can be redeemed into rewards, and prizes, such as free tickets or shopping vouchers. Some other gamification elements could also lead to monetary benefits, such as points being earned when winning mini-games.

4.1.2. HEXAD Results

Based on the questionnaire distributed in January–February 2023, 113 respondents answered, with the results of the participant distribution based on HEXAD summarized in

Table 5. HEXAD results.

Player Type	Result
Philanthropist	4.3
Disruptor	2.5
Free spirit	4.2
Achiever	4.1
Socializer	4
Player	4

.

Based on the results, the design elements according to the HEXAD type can be suggested, along with the top four types: Philanthropist, Free Spirit, Socializer, and Player. In addition, the types of gamification elements suggested are shown in

Table 6. Gamification elements form HEXAD.

Type	Gamification Elements
Philanthropist	Collection, gifting, knowledge sharing.
Free spirit	Exploration tasks, easter eggs, unlockable content.
Socializer	Teams work, social networks, social comparison, social competition, social discovery.
Player	Points, rewards, leaderboard, badges, virtual economy.

below [96].

4.1.3. Gamification Workshop

Participants input their ideas into the MIRO collaboration application during the program. The researcher subsequently engaged in discussion and inquiry into the proposals put forth by the workshop participants. Initially, numerous phrases in the game were unclear; however, following the participants’ explanation of the method, the outcomes could be summarized and included in the application design as a gamification element. Mini-games, including several variations, encompass concepts frequently proposed by participants. The results of participant collaboration through the MIRO application can be seen in Figure 2. Based on these results, gamification elements were selected to be applied to the application, as listed in the

Table 7. Gamification elements and digital nudge from the workshop.

Elemen GamifikasiGamification Elements	Digital Nudge
Point	Scarcity
Level	Loss aversion
Minigame/quiz
Reward/promotion
Mission /task/quest/challenge
Avatar
Easter egg/surprise reward
Progress bar
Social network
Virtual goods
Badges

.

4.1.4. Gamification Elements

The researchers conducted a systematic literature review to find elements usually used in transportation applications [55]. Based on the results of the SLR, several elements were found to be used, including points, badges, leaderboards, rewards, levels, and monetary incentives.

PBLs (points, badges, and leaderboard) were the most widely used elements, followed by rewards.

Table 8. Gamification elements justification from several gathering methods.

Gamification Elements	User Interview	HEXAD Questionnaire	Systematic Literature Review	Gamification Workshop
Point	✓	✓	✓	✓
Reward	✓	✓	✓	✓
Level		✓	✓
Monetary incentive	✓	✓	✓	✓
Mission		✓		✓
Mini-games				✓
Surprise gift/easter egg		✓		✓

shows the justification for the gamification features that have been implemented.

• Point

Points are applied to every successful trip made by passengers. Each passenger can earn some points. This element was applied according to the results of the SLR conducted by the researchers, where PBLs were elements that users often used. Based on the results of the interviews with the public transportation users, the thing they like most about using public transportation is that it is cheap and affordable. Points can symbolize the incomes they achieve for using public transportation, which are then transferred into monetary rewards. In addition, as in an experiment conducted in San Francisco-BART, points can also be used to reduce congestion during peak hours by giving extra points to passengers who choose hours before or after peak hours. Based on the experiment results, 10% of the respondents would choose travel times other than peak hours [107].

2.

Level

Levels indicate the achievements that application users gain after achieving a certain point value. At a certain level, users will earn certain rewards that are more profitable.

3.

Leaderboard.

As in other gamifications, the leaderboard shows a user’s position compared to other users. Leaderboards are usually used to motivate users to compete with other users.

4.

Rewards and monetary incentives.

In gamification, points collected can be redeemed as rewards that can be monetary, such as free tickets and vouchers, or non-monetary, such as recognition in the form of levels and badges.

5.

Mini-games

The existence of simple games that are easy for users to play and gain points on according to their achievements in the game can increase user enjoyment and engagement. This mini-game is expected to make the user experience more enjoyable. Mini-games in education can improve a student’s skills and increase engagement [108]. In addition, mini-games are a gamification element widely adopted by e-commerce platforms to increase user satisfaction [109].

6.

Easter egg/surprise

Once a day, when the user opens the application, the application will provide a surprise gift, such as extra points or rewards, so that users are motivated to use this application regularly.

4.1.5. Digital Nudge

The SLR digital nudge identifies various categories of digital nudges that can be utilized in applications [76]. The design of the digital nudge must be tailored to the application’s objective or problem domain. Interviews with government officials and public transport users indicate that the primary issue requiring resolution is enhancing public interest in public transport. Factors that can stimulate public interest include reasonable pricing. In assessing gamification features in public transport systems, elements that facilitate low fares or fees include the allocation of points and awards; hence, aspects associated with points and rewards may be enhanced to motivate users to utilize points more effectively.

The ideas for nudge design were then obtained through a literature study based on the types of nudges that have been synthesized by Weinmann, Caraban, and Valta [10,76,110]. Then, to gain understanding and inspiration, researchers conducted interviews with expert sources from UX practitioners. A total of 2 UX researchers from national and global companies were willing to provide input, and the study was conducted from October to November 2024 through video conferencing. This method followed what had been performed by [111] Mirsch when developing design methods for digital nudges. Contributions from practitioners are needed because there is still a lack of digital nudge research in academia and, likewise, not many practitioners are aware of the concept of digital nudges.

Based on the interview results, several nudges can be applied, including the following:

7.

Visibility

In the HOME view of the application (Figure 3), the number of points collected and the level/reward position that can be obtained are visible. This principle follows choice architecture, which means that information must be visible and easily accessible so that people can be influenced [112]. Visual cues play a crucial role in a display as they can attract the viewer’s attention. For instance, visibility can be enhanced in product displays at supermarkets by placing healthy products at eye level or allocating more space to them than other items. This approach increases the likelihood that consumers will notice and choose healthy products [113,114]. The influence of visibility on decision making is grounded in the “fast” System 1 reasoning, which “operates automatically and quickly, with little or no effort and no sense of voluntary control” [115].

8.

Framing

Mirsch states that framing nudges are among the most commonly examined nudges within information systems [1]. Thaler posits that framing can function as an effective nudge [13], given that individuals’ preferences may shift depending on how the decision context is structured or how the question is posed [116]. Framing can be categorized as either positive or negative. Positive framing highlights the benefits of performing a certain action, whereas negative framing emphasizes the adverse consequences of not taking that action [117]. For instance, “This vaccine effectively protects 95% of people from infection” exemplifies positive framing, while “Without the vaccine, you are 20 times more likely to get infected” represents negative framing. The framing employed in this application demonstrates a positive effect, as it emphasizes goal achievement rather than failure.

In the display of points, framing is performed so that users can read or capture the information presented differently. For example, say a user gains 40 points out of 100 points. The message can be twofold: (a) “you have reached 40 points” or (b) “60 more points to 100 points”. These two present the same information but can mean different things to the user [1,117]. Figure 3 shows the framing nudge on the application.

9.

Defaults

Defaults are arguably the most recognized and powerful method for influencing behavior through nudges [118]. Default nudges leverage the status quo bias by setting a particular option as the default choice. Since people tend to stick with their current state and are often reluctant to change their selection, default nudges become an effective tool for influencing decisions, such as increasing participation in organ donation or automatic retirement programs [13]. Status quo bias is a cognitive tendency where people prefer to maintain the current state (status quo) because it avoids effort and resists change, even though other alternatives may be more beneficial [119]. Therefore, default is one of the easiest designs to direct the user’s choice [120,121].

Figure 4 shows the default design in the app. In this design, defaults can be implemented in the reward display. For example, the application provides three reward options: free tickets, minimarket vouchers, or restaurant vouchers. The application wants the user to choose a free ticket so that the user will use public transport again. Therefore, the free ticket reward option will be the default.

4.2. Prototype

A prototype of a gamification and digital nudge application was proposed as part of an integrated public transport application in Jakarta. The gamification feature was implemented as a loyalty program feature. Here, a prototype view of the gamification element in the loyalty program feature is given. Figure 5 shows the user flow of the application.

4.3. Preliminary Evaluation

An evaluation involving users was carried out in 2 iterations. In addition to running tasks/scenarios, respondents were also asked to perform a think-aloud task.

4.3.1. First Iteration

In this usability test, respondents were not given a structured list of tasks. The researcher gave them the application and asked the respondents to try it after explaining its function. Then, the users performed the think-aloud task. In this second iteration, because the prototype already resembled the actual application, respondents received a more real experience. This test involved two respondents, according to [101]. For finding problems in usability testing, involving five respondents is deemed sufficient.

Some of the inputs given by respondents included the following:

• Fleet-tracking features used for real-time fleet tracking.
• Prizes/rewards in gamification related to public transport and other prizes, such as shopping vouchers.
• Social media on the app to allow users to share information about what is happening during the journey.

4.3.2. Second Iteration

Based on the suggestions from the first iteration and the interviews with expert practitioners in the UX field, several improvements and digital nudge elements could be made to the gamification elements. At this stage, we carried out the method reported in the research conducted by Horsham and Vilardaga [43,45], among others:

• Users can interact with the application and run scenarios according to the given task.
• Users conduct think-aloud tasks and interviews related to their experience using the application.
• Users fill out an SUS questionnaire.

The SUS questionnaire was conducted on two versions of the application: version A, a gamification application without a nudge, and version B, a gamification application with a nudge. The participants completed the SUS questionnaire after executing tasks during the usability testing.

Table 9. SUS questionnaire results for apps without nudge.

Respondent	SUS1	SUS2	SUS3	SUS4	SUS5	SUS6	SUS7	SUS8	SUS9	SUS10	SUS Score
R1	5	3	4	1	4	2	4	2	2	1	75
R2	4	1	5	2	4	2	4	1	4	3	80
R3	5	1	5	1	5	2	5	1	4	2	92.5
R4	5	2	5	1	4	4	4	2	4	3	75
R5	5	4	4	1	4	2	4	2	4	2	75
R6	4	2	4	4	4	2	4	4	4	4	60
R7	5	1	5	3	4	2	5	1	5	3	85
R8	4	2	4	2	4	2	5	3	2	5	62.5
R9	3	2	3	3	4	3	4	2	2	3	57.5
R10	5	1	5	1	4	4	4	4	5	2	77.5
											74

and

Table 10. SUS questionnaire results for apps with nudge.

Respondent	SUS1	SUS2	SUS3	SUS4	SUS5	SUS6	SUS7	SUS8	SUS9	SUS10	SUS Score
R11	4	2	4	4	4	4	4	4	3	4	52.5
R12	3	2	3	3	3	2	3	2	3	3	57.5
R13	4	3	3	5	4	3	2	4	2	5	37.5
R14	5	2	5	1	5	1	5	1	5	1	97.5
R15	4	5	4	5	4	5	4	5	2	4	35
R16	4	1	5	1	4	2	5	1	5	1	92.5
R17	4	2	4	2	4	2	4	2	4	2	75
R18	5	5	5	5	5	5	5	5	5	5	50
R19	4	2	4	5	4	4	4	2	4	5	55
R20	4	1	4	1	4	4	5	2	4	4	72.5
											62.5

present the SUS questionnaire’s outcomes, including the SUS score calculations.

In the interpretation of the SUS value, according to Tullis and Sauro [122,123], based on studies conducted using the SUS questionnaire, the average SUS value obtained by websites and applications is 66. So, based on that SUS value, version A of the application, with a value of 74, can be said to be above average, while application B, attaining a value of 62.5, is below average. Another research study states different thresholds; it can be determined that application A is classified as acceptable, while application B is under the threshold [124]. These results show unsatisfactory results, but the SUS value of a product can change dynamically according to the product’s life cycle. At the beginning of the product cycle or product introduction, the SUS value tends to be lower because respondents do not know the product well [124].

Based on the results of the SUS questionnaire, the value obtained for version A of the application is still above average (74), and version B is still below average (62.5). This result shows that many improvements to this application are still needed. This result aligns with the SUS value of gamification applications related to lifestyle, which received a score of 70 [125]. The SUS result of the exergames application also shows a score of 70 [102]. When examined more deeply, the difference in the range of SUS values between respondents is quite significant. This can occur due to differences in perceptions between respondents, especially respondents who rarely use public transportation and expend more effort to switch to public transit regularly.

A recent study performed by another author conducting usability testing on a Jakarta public transport application, which is the most downloaded on Playstore, also found an SUS value of 67 [126]. This result aligns with the SUS value obtained in the initial evaluation of the public transport gamification application. This suggests that changes and improvements should be made to the design and user experience based on the feedback from respondents [127].

The results were then transcribed based on the interviews with respondents during usability testing. Then, a researcher carried out a thematic analysis by following an iterative process to familiarize themselves with the data, generate initial codes, search for themes, determine and name themes, and review the themes.

Table 11. Thematic analysis from usability testing.

Theme	Quote
Purpose of using public transportation	P1: To campus, yesterday when I was doing my internship, I also took the busway
	P4: Like going to tourist attractions, to the city, to the mall, if you have free time like that
	P5: Well, so the story is, my friend and I wanted to go to Blok M. [………….]. So we took the MRT. Then we took the KRL too. So I think taking the MRT and KRL is nice and cheap too.
Public transportation app features	P1: he can provide not only one mode of transportation, […….], but also integrated with other transportation methods
	P4: Go Transit is also quite clear. Yesterday I wanted to try to go to Bekasi, that was clear. Then I wanted to try to go to Palmerah, transit to Tanah Abang, that was also clear.
	P7: It’s easier, since there’s Google Maps.
	P9:But he can track like that if JKL wants to come
	P11: Payments are easier, because we use QRIS and e-wallet.
	P14: Time estimation. There can be many choices, right? Which time is the fastest?
	P17: What I like is the payment feature.
	P17: So yes, if it can be tracked in real time,
Attractive design and color	P2: From the JKL application, the colors are nice, right, Sis?
	P4: It seems easy, delicious, simple.
	P6: The color is not that striking.
	P8: From the looks of it and the features inside
	P9: I like the color.
	P18: It’s cool. I saw earlier that it looked cool colorful.
Easy-to-use application	P2: Then this is like according to our habits. For example, if we want to go to info, the one below, the one on the right.
	P6: The display is also easy to use; it shows what you want to click. If we want to pay, there is already a logo somewhere. If we want to show the ticket, where is the barcode, it is already clear.
	P9: Then the display looks like it’s easy, it makes it easier for us to travel.
	P18: We click on this, this appears, it’s that simple.
	P13: Be less long-winded, okay?
Small display	P2: The writing is small, and the images are blurry, not HD enough.
	P9: Does this writing seem too small? What if it’s not enough for parents?
Recommended features	P2: Just add it, like if we go to Blok M there are lots of destinations, add it like top search
	P15: In my opinion, the lack of integration is the lack of online ones, like Gojek or Grab.
	P16: Most likely in the ordering feature. Because earlier, to order, you had to search first, right?
	P18: Maybe a filter can be added for bus tracking. […]. Then if there are customers who want to complain or ask questions, there can be a CS who can be directly connected to Whatsapp.
Proof of concept: Points and reward	P1: So maybe with this gamification, they will be motivated to continue using it.
	P2: It’s the same, it says there are points here. […] That’s good, Sis. There’s also gamification here.
	P8: […] then we get coins if we use it.
	P9: Then I found out that there were points, that also seemed fun. You can collect points to get prizes, and that seems fun.
	P16: What I like is that there is a redeem. That seems quite interesting. This means that if I use the application often, I will receive other benefits.
	P10: Maybe the types of prizes could be more varied.
Proof of concept: Mini-games	P1: I saw earlier that there was gamification, but the gamification here is still in the form of a game. What kind of game is that?
	P2: There is also gamification. So when you are in transportation, you won’t get bored, especially if you are an introvert. You don’t want to be talked to right and left, so open the game here.
	P10: Then there’s gamification, too. Maybe if we’re waiting or something, we won’t get bored. So I like it.
	P18: If you’re bored, you can play games on this application.
Proof of concept: sustainability	P10: Because it displays the amount of carbon. So it’s more for awareness.

shows the results of the thematic analysis.

4.3.3. Usability Testing Analysis

Based on the results of the SUS score, which was still below the standard, several improvements can be made based on the interview results. The respondents were still not satisfied with the appearance of the application. This result is revealed by several things mentioned, such as images and writing, “The writing is small, then the pictures are blurred, less HD”. One of the goals of usability testing is to find usability problems, such as the appearance of the user interface (UI) [102]. This opinion aligns with another research study [128] with a reasonably high SUS value (80); for that application, respondents liked the UI display.

The SUS value was also still possibly lacking due to the respondents’ lack of satisfaction with the features displayed. Table 11 lists some suggestions and criticisms from respondents regarding features that are still needed. For example, “maybe a filter for bus tracking can be added.[…]. Then, if a customer wants to complain or ask a question, there can be a CS that can be directly connected to WhatsApp”.

This study also presents a limitation because it was unable to optimize the application. After all, this application was not connected to the system in the real world, causing respondents to feel unable to have a real experience of using this system.

In addition to the shortcomings of this application, based on the interview results, a proof of the concept of gamification was also obtained. Some emerging themes were drawn based on gamification elements in the application, including mini-games, points, and rewards. As expressed by respondent P1, “So maybe with this gamification they will be encouraged to continue using it”, and respondent P16, “What I like is that there is redeem yes. That’s kind of interesting. This means I will get other benefits if I use the app often”. It can be seen that this element motivates users to continue using public transport.

In the proof of concept of mini-games, several respondents responded that mini-games can be played to relieve boredom. “If you’re bored, you can play games on the application”. Respondents felt that mini-games could make them more involved with the application. Based on the results of previous research [91], through its elements, gamification can indeed increase engagement with its users. Games on non-game applications are not uncommon; games like Pokémon GO are also used to influence people’s transportation choices, encouraging those who usually use private vehicles to use public transportation [129].

Transportation is closely related to the concept of sustainability [44]. The carbon print feature has been displayed on the route feature by displaying route recommendations with carbon print-saving data, as stated by respondents, “because it displays the amount of carbon. So it’s more for awareness, right”. It is hoped that the public will be more aware of the environment with the carbon print feature. A recent study also applied a pro-environmental label to the transportation mode selection feature, considered to be a nudge that can influence users to choose a more sustainable mode [17]. The gamification element is closely related to influencing passengers to use public transportation by implementing points and rewards in the public transportation application’s loyalty program [50]. Likewise, in a study in Denmark, the point element was used to encourage people to choose a more sustainable mode of transportation and was proven to influence passenger intentions [14]. In literature studies, points are also the most widely used gamification element in transportation applications [130].

The SUS score for the gamification application with digital nudges surprisingly achieved a lower SUS score than the gamification application without nudges. This result is different from the results of nudge research on social media, which showed that nudges (notifications) showed a higher difference in IUS (Intervention Usability Scale) scores than without nudges [131]. Meanwhile, in other studies, the SUS score was only applied to 2 different nudge experiments, so no evidence on the difference in SUS score between non-nudges and nudges was available [132,133]. However, other studies show that the SUS score for applications without nudges is greater than with nudges. This can happen because the presence of nudges adds excessive friction to the user experience [105]. We argue that during the experiment, users did not experience authenticity; for instance, they did not receive real rewards. This situation directly impacts their perception of the application’s usability. Additionally, excessive friction in applications featuring nudges raises concerns that it may lead to users being reluctant to accept these nudges. Therefore, it is recommended that applications with nudges conduct quantitative and qualitative usability testing to find usability problems and make improvements to the next version.

5. Conclusions

Limitations and Future Research

While this study offers valuable insights, it is not without limitations, which future investigations should seek to overcome. First, since the public transport application is still a working prototype version, there are shortcomings in functionality, system stability, and application interoperability, which can also be an obstacle to observing the real effects of gamification or the digital nudges applied. An essential requirement for complete implementation and testing is integrating real-time data into the public transportation system, which is now unattainable. This constraint is prevalent in travel and transport research, leading researchers to adopt alternative evaluation methods, such as pilot studies [134] or simulations [135]. This research lacks quantitative and longitudinal data, so it cannot be generalized quantitatively. However, this can be balanced by the depth of qualitative data collected through the interviews.

The limited research sample in terms of respondents’ backgrounds also presents a barrier to the implementation of this technology. If possible, further research could apply this application to the real world so that real experiments can be carried out and real data can be collected. Applying the technology to real situations could make the samples more numerous and heterogeneous. Future research should adopt continuous and long-term approaches to generate longitudinal findings.

Another limitation that should be noted is that applications including gamification and digital nudging have the potential to effectively engage public transportation customers and encourage them to stay interested in using public transportation. Nevertheless, gamification and digital nudges are not panaceas capable of offering a comprehensive solution. First, specific criteria must be met, including the quality of public transportation, punctuality, extensive route availability, safety, and convenience. As shown in the thematic frequency figure (Figure 1), convenience is the theme that appears the most, so it is the most significant factor influencing people’s intention to use public transportation. Insufficient fulfillment of these specifications would pose challenges for the government in promoting the use of public transportation.

Digital nudging is a field that recently emerged within behavioral research. In future research, potential new digital nudge elements remain to be identified by academics. Public transport usage is intricately linked to principles of sustainability. Furthermore, the gamification design in this work incorporated features that demonstrate the utilization of carbon prints. In subsequent studies, one may investigate the impact of carbon footprint information on the extent of public consciousness regarding environmental and sustainability concerns.

Finally, this research also opens opportunities to examine new trends in information systems. In this study, the researchers conducted a thematic analysis manually by summarizing the results in Excel and processing frequency data using Excel tables. This approach was employed due to variations in research skills between the researchers and research assistants. Currently, for this study, there were opportunities to conduct thematic analysis using artificial intelligence (AI) tools. With these tools, bridging the differences in skills and objectivity between researchers may be possible. The study by De Paoli [136] is a valuable reference for applying thematic analysis with the help of generative AI tools like ChatGPT-4.

Regarding data sovereignty, implementing digital nudges and gamification involves collecting user data, which can create reluctance or fear of sharing personal information. However, with the future integration of Web3 technologies, users will have full control over their own data. Web3’s decentralized architecture could reshape Internet governance by shifting control from centralized platforms to individual users [137]. This transformation would give users more power over their digital identity and data ownership. When users are confident that their data are used securely, it increases the acceptance rate of digital nudges. It also opens up opportunities to design more ethical, transparent, and trustworthy nudging, thus supporting more responsible digital interactions in public services such as transport.