Developing serious games for health is challenging since it involves combining serious and entertaining goals, involves large-scale software development with a multidisciplinary team, and the users are not identical [28]. The P-III framework mitigates these challenges by providing a player-centered, iterative, and integrated approach to designing and developing serious games for health with a multidisciplinary team [27]. The framework was established through research projects where it was formed, designed, verified, and refined [29]. The framework consists of 4 conceptual pillars.

To create games that meet the needs of the target group, players are involved in the entire process of game design and development, rather than involving them only in the usability testing phase [27,30,31]. The process is based on the human-centered design process [32-34].

The game is designed and developed iteratively and with three phases (Figure 1) [27] as follows: (1) concept design to understand the player group and the problem domain, (2) game design, where the game concept is transformed into a detailed game, and (3) game development, where a prototype is built and tested with users.

In addition to software engineers, visual artists, project managers, and game designers, serious game production requires the expertise of social scientists and other subject matter specialists [27].

The serious content is integrated with the play as closely as possible [27]. The development is based on theory-driven and evidence-based frameworks [35] and should focus on integrating serious content [36].

This viewpoint summarizes the design and development process of a mobile exergame Heart Farming [37] using the P-III framework to share the phases in the process so other health app developers and scientists might reuse or extend the process.

The exergame was developed by an interdisciplinary team consisting of a development team (1 game designer, 1 usability expert, and 2 programmers), stakeholders (as domain experts, patients with cardiac disease, and users who were not patients with heart failure called “healthy” users), and users (patients with cardiac disease and users with no cardiac disease; Figure 2). The exergame was developed through 7 iterations until it was safe, efficient, and entertaining (Figure 3). All iterations included deployment and evaluations, so the exergame was continually tested by the team. All iterations included deployment and evaluations, so the exergame was continually tested by the team. In each iteration, new patients and “healthy” users (who are not patients with heart failure and do not know if they have any other diseases) participated in testing and evaluations. In this section, we summarize the iterations.

The serious game P-III framework [27] needs to be modified in order to be used for the design and development of exergames for health. In Figure 6, we propose an update of the framework adapted for developing exergames that includes three phases: (1) physical activity and interaction design, (2) concept design, and (3) game design and development. The update is inspired by the human-centered design process [32-34] that involves an iterative cycle in four steps: (1) specify the context where the product will be used, (2) specify the user requirements, (3) produce design solutions, and (4) evaluate solutions against these requirements.

We used the serious game P-III framework [27] to design and develop an exergame that need to meet the needs of patients with heart failure [37]. The exergame was developed in 7 iterations.

Since the P-III framework [27] is developed for serious games, in general, it lacks focus on the physical activity and physical interaction design process which is required early in the process of designing exergames. The primary purpose of many exergames is to promote and increase physical activity, and consequently, enhance health [15]. An efficient exergame guarantees that players can reap the desired health advantages. Developers can make sure that the exergame successfully serves the stated health and fitness goals by giving the physical activity component top priority early in the design process and continuously during the development process. Exergames require certain key technical components like motion detection [51], gesture recognition [51,52], and feedback mechanisms [43]. By beginning with physical activity, developers can address these technical issues early in the design process and make sure that the selected technology is in line with the planned player experience. By emphasizing movement and interaction in design, exergames can be made more enjoyable and engaging for players over time by encouraging them to be physically active [43]. Exercise mechanisms can be smoothly incorporated into the exergames by developers if they begin with an emphasis on physical activity. This guarantees that the movements needed for fitness are in line with the goals of the exergame, enhancing the gaming experience.

Evaluations were conducted during each iteration by both the team and users or patients. All concepts and prototypes were reviewed and tested by the interdisciplinary team and target audience. This is in line with the player-centered design approach [27,30,31]. Since the exergame was developed for a smartphone, the evaluations were not solely done on the development computer but also on the intended platforms; Android and iPhone smartphones that support augmented reality. New features were first tested on a desktop and then on the intended platform. By using player simulations to assess the exergame on the desktop with the intended use, development productivity was boosted as testing on the intended platform is typically expensive.

Taking physical activity into account from the beginning enabled the team to handle safety and health issues and take these aspects into consideration during the concept design. The physical interaction is impacted by the platform. Therefore, it is essential that the exergame is continuously deployed on the intended platform to be evaluated so the evaluation is not solely done on the development computer. Using prototypes is good but not sufficient [53] since they serve as the embodiment or rudimentary exploration of concepts and ideas to assess their inherent potential [54]. Interfaces, screen sizes, and input techniques differ throughout systems. Further, prototypes can also be used to explore one area at the expense of another [55]. For example, a technical prototype is made without considering the user experience in order to establish the technical capabilities [55]. Therefore, developers need to evaluate the player experience in the actual setting where the exergame will be played by testing on the target platform. This entails taking into account elements like ergonomics, reactivity, and visibility. Previous research about understanding the relationship between technology and users has shown that deployments are crucial to research investigation [53]. Deployments enable users to use the technology over time in the intimate and disputed situations of daily life which reveals to design research teams the extent to which specific features of the technology are successfully attained [53].

Developing the exergame in an interdisciplinary team was found to be important to ensure that the exergame met the patients’ needs. Stakeholders can be involved in any, potentially multiple, of the following roles [36]: (1) users: stakeholders are treated as users and are involved in the beginning or end of the process, (2) testers: stakeholders test concepts, prototypes, and possible alternatives so the team gets relevant feedback early to improve the game quality and reduces the overall cost of the project, (3) informants: stakeholders act as consultants to the team by sharing ideas during the process, and (4) design partners: stakeholders are involved in contributing to the game design, so prototypes are developed collaboratively.

Having stakeholders with different roles (eg, as domain experts testing the exergame during evaluation, providing information about the patients during concept design, and acting as design partners during the physical activity and interaction design phase) helped the development team to keep the focus on the patient’s needs and to design and develop an exergame that meets these needs. According to Mildner and Mueller [36], constant collaboration with stakeholders helps to keep design efforts on track. As for the P-III framework [27], interdisciplinary teamwork is an important pillar for designing and developing exergames. In our study, we had many iterations with quick turnarounds and feedback from stakeholders, so patients and “healthy” users were included in all phases. As recommended by Pirovano et al [56], users who were not patients were included as they could provide relevant input and were easier to recruit than patients. However, interpretation of evaluation results needed to be made by keeping the target patient group in mind.

Further research is needed to test the exergame with different patients and to implement and investigate the feasibility and effectiveness of using the exergames by the target group, older adults with heart failure.

The P-III framework for serious games was applied for the design and development of an exergame for patients with heart failure. A mobile exergame was developed iteratively in 7 iterations with the inclusion of continuous evaluation by the team and with stakeholders. During the development, stakeholders had different roles that helped the development team to keep the focus on the patient’s needs and to design and develop an exergame that met these needs. Based on our case study, we propose an updated version of the P-III framework for exergame design and development: (1) inclusion of separate and thorough prototyping of the physical activity and physical interaction design with high-fidelity prototypes and user testing, and (2) launching the exergame as soon as possible and continuously on the intended platform to enable evaluation and everyday life testing.