Android phone users (ages 18+ and fluent in English) can earn up to $15 for testing out a beta-version of an app and providing detailed user feedback. You will be asked to download and use an app on your smartphone designed to help people track their thoughts at random moments across 10 days (1-1.5 hours total usage time). For more information, please send an email with subject line “Android Study” to the research team at archlabcalendar@gmail.com.