Designing Social Features in Physical Activity Apps for Generation Z by Integrating Behavior Change Techniques and Persuasive System Design Principles.

Lukas Dommershausen (2024): Designing Social Features in Physical Activity Apps for Generation Z by Integrating Behavior Change Techniques and Persuasive System Design Principles. In: University of Salzburg: Thesis.

Physical inactivity is a major public health concern among Generation Z, with fewer than 20% meeting recommended physical activity (PA) guidelines. Digital Health Interventions (DHIs), such as PA apps, offer potential for sustained behavior change, yet user engagement remains low. This study examines how combining Persuasive System Design (PSD) principles and Behavior Change Techniques (BCTs) can design social features in PA apps that foster relatedness among Generation Z. It explores how these features are perceived across different motivational profiles to promote behavior change and motivation internalization. A three-phase approach was adopted and included: (1) a literature review to develop user archetypes based on Generation Z’s behaviors and motivations; (2) a co-creation workshop with designers using these archetypes to design social app features integrating PSD principles and BCTs; and (3) a mixed-method evaluation with Generation Z participants, analyzing the features´ persuasiveness and potential for fostering relatedness. We gathered feedback from 150 participants via an online questionnaire. Insights from the first two phases revealed that while PSD principles and BCTs were useful for creating social features in PA apps, designers struggled to establish a clear mental model linking relatedness to social mechanisms of the two frameworks, leading to adaptations during storyboard creation. The third phase highlighted that face-to-face contact, especially with friends, appealed to all user groups. Cooperation and social learning also showed potential for fostering relatedness and motivation. Externally regulated users were prone to ego-involvement through recognition and comparison, while intrinsically motivated individuals resisted social cues hinting at external validation, aligning with their autonomous motivation. This research advances Human-Computer Interaction (HCI) by integrating BCTs and PSD principles with Self-Determination Theory, offering insights for designing PA apps that promote relatedness and intrinsic motivation for sustained behavior change.