Purpose Existing solutions facilitating mobility among older adults mainly focus on supporting physical disabilities. However, solutions are more likely to succeed when current activities and capabilities serve as a starting point. Participatory design is a suitable approach to detect these. We investigated (i) how participatory design techniques can be applied to obtain insight into the daily activities and capabilities of older adults, and (ii) what the design implications are of taking these activities and capabilities as a basis for the development of a mobility-enhancing application. Method Research context was a three-year European project comprising health care managers, researchers, and designers from Belgium, the Netherlands, Italy, Spain, and Germany. Older adults were involved in each of the four-step iterative design process (participatory design sessions, scenarios, user requirements, and user evaluation). Results & Discussion (i) Reflection on the design process showed that particular issues should be considered in selecting participatory design tools (e.g., diaries and photo assignments are more suited than interviews) and organizing joint sessions (e.g., reserve more time for informal activities, address privacy concerns, and provide opportunity to ventilate doubts towards technology). The participatory design methods appeared suited to provide input for the application’s functionalities based on activities and capabilities. (ii) A mobility-enhancing mobile application for older adults should apply (a) Demographics: validated user profiles as a basis, but enable personalization; (b) Cognitive and physical abilities: Facilitate activities close to the home of the older adults; (c) Safety perception: Support older adults cognitively during their activities outdoor, but also prior to and afterwards and foster social contact. Future work The results of the current study have been used as input for prototype development, which has been tested in a pilot study in Spain and The Netherlands."