A Study Evaluating An Integrated Pharmacy Digital Diary and Delivery Strategy to Increase PrEP Use Among MSM and TGW

Inclusion Criteria: * Age 18 years or older * Assigned male at birth who reports sex with persons assigned male at birth * Willing and able to provide written informed consent * HIV-uninfected by negative 4th generation HIV test during screening * Owns a smartphone and has private access to the internet * Able to understand, read, and speak English or Spanish * Lives in California * Self-reported evidence of being at-risk for HIV acquisition, including at least one of the following in the past 6 months: * ≥ 1 episode of anal/vaginal sex with a male or transgender female partner; * Diagnosed with a bacterial sexually transmitted infection (STI). * Interested in taking daily TDF/FTC or TAF/FTC PrEP * Willing and able to receive PrEP prescriptions through Alto Pharmacy (e.g., no specific pharmacy required by health plan, such as Kaiser HMO) * Creatinine clearance \>30 mL/min * No contraindications to TDF/FTC or TAF/FTC use Exclusion Criteria: * Repeatedly reactive HIV test at screening or enrollment * Signs or symptoms of acute HIV infection at screening or enrollment * Currently enrolled in another HIV intervention study. * Unable to commit to study participation for the duration of the study * Any medical, psychiatric, or social condition or other responsibilities that, in the judgment of the investigator, would make participation in the study unsafe, complicate interpretation of study outcome data, or otherwise interfere with achieving the study objectives.