There is a critical need to better understand the epidemiology of HIV acquisition in the United States (US), particularly among young men, one of the key populations essential to target for End the HIV Epidemic (EHE) initiatives. In direct response to RFA-AI-21-018, this study will use innovative technology to recruit and retain a large cohort of young men from HIV prevalence geographic areas (known as “hot spots”). Furthermore, we will leverage this cohort to conduct a large-scale clinical trial while maintaining the standard of care control arm as a longitudinal observational cohort for epidemiologic analyses. Our study team is uniquely positioned and has all the relevant expertise to conduct this study having successfully recruited and retained more than 12,000 young men in a full range of research studies across the HIV continuum (e.g., epidemiology, intervention development, mHealth, PrEP, clinical trials, innovative geospatial methods). We have had specific success conducting prevention research with young men. Further, we have previously leveraged advanced social media advertising techniques and used innovative geospatial analytics to studies “communities within communities”, reaching hard-to-reach young men from various geographic areas (e.g., rural zip codes, U.S. tribal lands, etc.) and young ages (e.g., 13-18 years of age). We will harness innovative technology to and retain a large cohort of young men and follow them every 6 months thereafter. We will conduct an entirely virtual, digital clinical trial testing whether MyPEEPS Mobile (an evidence-based mHealth HIV prevention intervention) reduces HIV incidence among young men looking at the influence of theory-driven social, ecological, and geospatial factors on intervention uptake and efficacy inclusive of measures that align with traditional models of behavior change such as the Information Motivation Behavior Model. A social-ecological theoretical framework will also guide the analysis of the longitudinal observational cohort study to understand individual, network, geospatial, and public policy correlates of health seeking behaviors comparing individuals who become HIV-positive to those who do not. Findings from this research will have important real-world implications for research and practice. For example, understanding how individual, network, geospatial, and public policy factors correlate with HIV incidence and moderate intervention effects will help inform how and where interventions should be delivered.