Feasibility, Acceptability and the Effects of Two Publicly Available Physical Activity Mobile Apps

The aim of this research project is to investigate the feasibility and acceptability of a study assessing 2 selected PA apps to inform the design of a definitive randomised controlled trial, and to assess the effects of the app interventions on PA. To address the aim, an explanatory mixed‐methods study using quantitative (phase 1) and qualitative (phase 2) design will be used. Target population will be those that do not engage, or engage in low levels, of PA and the investigators will aim at recruiting participants from London and surrounding areas. The primary objective is to determine the feasibility and acceptability of the trial procedures and the interventions delivered using apps. The secondary objectives are to explore potential effects of the 2 selected PA apps on behavioural and psychological outcomes, and to assess the usability of the apps. Phase 1 Phase 1 will utilise a crossover which means that half of the participants will be randomly assigned to use 1 of the 2 apps, while the other half will use the 2nd app. After 2 weeks participants will switch. Participants will complete a baseline assessment (1 week), followed by the randomisation to using 1 of the 2 apps (2 weeks' follow up), and crossover (4 weeks' follow up). The primary outcome of the study will be average percent increase in activity count and will be measured using accelerometer. The secondary measures include exercise self‐efficacy, intentions, apps usability and usage. Phase 2 Following the end of phase 1, a semi‐structured interview will be conducted to explore the acceptability and experiences of using the 2 apps (phase 2). The sample will include participants that took part in the crossover trial and consented to being interviewed. Participants that showed frequent usage of the apps, as well as those who used the app infrequently and/or discontinued using the app will be interviewed.