Your participation in this study is completely voluntary. If you choose to participate, you will be asked to (1) download the 3E Smartphone Substudy app and allow sharing of your smartphone data and (2) complete short, daily surveys for 9 days in a row. Surveys will be administered in the 3E Smartphone Substudy app and take ~5 minutes to complete. The surveys will include questions about your sleep, physical activity, and other health behaviors that day. The app will collect information from your smartphone’s built-in GPS, accelerometer, and gyroscope sensors to give us information on your movement (e.g., steps and distance traveled). It will also collect general screen time and app usage data (e.g., how long you use). It will NOT collect information from your text messages, phone calls, or your apps beyond which app you are using and for how long (e.g., Spotify for 50 min). If you choose to participate, we will ask you to complete this process 1-2 times per year. You will receive up to $35 for completing the 3E Smartphone Substudy.