Background Hazardous alcohol consumption, and binge drinking in particular, continues to be common among college students, posing the greatest risk for their health and safety. Despite widespread exposure to evidence-based preventive interventions among US undergraduates, only modest and temporary effects on risky drinking occur. Formative studies have demonstrated that students want a more engaging intervention tool for risky drinking that can be used just in time. Objective The purpose of this study is to test the appeal, relevance, and perceived utility of a draft mobile app for safer student drinking at a public university in Virginia. Methods Undergraduate student participants tested the draft mobile app via a web-based prototype that tailors to individual feedback with hot spots that responded to their taps to mimic app functionality. They narrated their impressions, navigation, and comments in a standardized think-aloud procedure. After each round of think-aloud interviews, researchers debriefed the investigators and developers to discuss findings and brainstorm app modifications. Results Minor changes to the functionality and aesthetics would improve usability of the app (eg, option for light mode in app settings). Student testers recommended tailoring the app to the needs of college students and to aspects of the local university’s drinking culture. Conclusions Findings from this study will be synthesized with information gained from other formative work to determine the final app features. We will test the app in a pilot randomized trial to assess app use and the impact of the app on college student drinking behavior over several months.

BACKGROUND Hazardous alcohol consumption, and binge drinking in particular, continues to be common among college students, posing the greatestrisk for their health and safety. Despite widespread exposure to evidence-based preventive interventions among U.S. undergraduates, only modest and temporary effects on risky drinking occur. Formative studies have demonstrated that students want a more engaging intervention tool for risky drinking that can be used “just in time.” OBJECTIVE The purpose of this study was to test the appeal, relevance, and perceived utility of a draft mobile app for safer student drinking. METHODS Undergraduate student participants tested the draft mobile app via an interactive online prototype with hot spots that responded to their taps to mimic app functionality. They narrated their impressions, navigation, and comments in a standardized Think-Aloud procedure. After each round of Think-aloud interviews, researchers debriefed the investigators and developers to discuss findings and brainstorm app modifications. RESULTS Data indicated that minor changes to the functionality and aesthetics would improve usability of the app. Student testers recommended tailoring the app to the needs of college students and to aspects of the local university’s drinking culture. CONCLUSIONS Findings from this study will be synthesized with information gained from other formative work to determine the final app features. We will test the app in a pilot randomized trial to assess app usage and the impact of the app on college student drinking behavior over several months.