The purpose of the Ohio Study application is to enable participation in the Ohio Study, conducted by researchers at The Ohio State University. The Ohio Study is intended for adolescents 13-17 years of age and investigates how adolescents’ daily activities, relationships, and social media habits influence their mental and physical well-being. This application will make it possible to estimate the time spent using the smartphone, the type of activities and applications used on a daily basis (e.g., social media, messaging, streaming) as well as the places you go. Questionnaires will also be sent to the application to learn more about the mental and physical well-being, lifestyle patterns, and personal characteristics of the participants. The knowledge gained from this study will provide the information needed to develop effective interventions aimed at promoting the mental and physical well-being of adolescents.