Canadians who identify as women are less likely to take part in sport and physical activity compared to people who identify as males (Canadian Women and Sport, 2020). However, mobile tracking applications can increase women's participation in physical activity by providing guidance and feedback for exercise (Voskuil et al., 2020). ParticipACTION is a non-profit organization that has created a mobile application designed to educate and encourage Canadian adults to engage in more physical activity (Truelove et al., 2020). The aim of this research was to examine how users' physical activity is related to their mobile app use. Using a mixed-methods research design, participants (n = 3,183) completed a survey regarding their use of the app, current activity levels, motivation to use the app, motivation for physical activity, and self-efficacy for physical activity. Nine focus groups were conducted with 37 participants to discuss their use of the mobile app in more detail. Quantitative results showed a significant, positive correlation between duration of app use and duration of physical activity, however, results also indicated that participants still did not meet the recommended physical activity guidelines for Canadian adults. Qualitative results highlighted participants' likes, dislikes, and recommendations for more community and social engagement in the mobile app. In conclusion, mobile applications may have some benefits for improving women's physical activity, but more research is needed to examine how app use can causally increase actual physical activity.