This study seeks to understand substance use and other health behaviors in young adults' daily lives. Interested participants can email the study team to complete a brief screener to see determine their eligibility. If eligible, participants will be asked to complete a short online survey and follow-up surveys for up to four weeks via a mobile device. Financial compensation will be provided.

This study involves three parts. First, potential participants will complete an online screener survey. If they are eligible, they will be immediately enrolled in the study and will proceed to the baseline survey. Second, participants who have completed the baseline portion of the study will schedule an in-person visit with the research team for the next portion of the study. At the start of the in-person visit, participants will be oriented about the study design which involves completing daily surveys about various health behaviors. Third, participants will come back in-person for a brief final visit and receive payment.

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