User experience and usability requirements of a physical activity smartphone application for wheelchair users with spinal cord injury

Usability considerations for wheelchair users remain underexplored. This study evaluated usability requirements of a smartphone App (MvBii) for monitoring physical activity and sedentary behaviour in manual wheelchair users with spinal cord injury (SCI). A mixed-methods design was adopted. Manual wheelchair users with SCI completed System Usability Scale, e-loyalty and user experience questionnaires, think-aloud sessions and scenario-based workshops. Six design and research evaluators undertook think-aloud sessions. Qualitative data was analysed thematically and mapped against heuristics. Ten participants with SCI (C5-L1; three females) with a mean age of 51 ± 9 years took part. The App received positive ratings on e-loyalty (mean scores, 5.6 ± 1.51 to 6.10 ± 0.99 across items) and user experience (4.3 ± 1.03 to 5.93 ± 0.78) from participants with SCI. A novel heuristics principle was developed to explore “accessibility and inclusion” usability issues. Thematic analysis captured patterned meanings across tasks and heuristics including “Navigating with autonomy” (e.g., challenges with interface clarity and understanding terminology), “Language and representation” (e.g., simplifying using inclusive language and icons), and “Seeing progress not noise” (e.g., physical activity notifications that encouraged self-competition without external pressure). This study demonstrates the value of a mixed-methods approach to usability and heuristic evaluation for identifying effective, accessible and inclusive tailoring of physical activity Apps universally and for wheelchair users specifically. These findings can inform refinements to the MvBii app and provide broader insights for designing inclusive and effective mobile health Apps across diverse populations. Wheelchair users with spinal cord injury demonstrated high intention to use the physical activity smartphone App.Key usability issues were identified that should be considered in physical activity Apps include interface clarity, terminology, and visual accessibility.A novel heuristic principle was proposed that will aid in effective design for accessible digital experiences.Recommendations for physical Apps for wheelchair users include enhanced customisation, inclusivity and simplified language. Wheelchair users with spinal cord injury demonstrated high intention to use the physical activity smartphone App. Key usability issues were identified that should be considered in physical activity Apps include interface clarity, terminology, and visual accessibility. A novel heuristic principle was proposed that will aid in effective design for accessible digital experiences. Recommendations for physical Apps for wheelchair users include enhanced customisation, inclusivity and simplified language.