Differentiated service delivery (DSD) increases antiretroviral therapy (ART) access in sub-Saharan Africa (SSA) by moving patients out of congested ART clinics to communities for care. Patient outcomes in DSD and traditional clinic-based care appear similar at lower cost. Decreased donor funding, health system constraints, healthcare worker (HCW) shortages, and COVID-related calls to reduce clinic visits, push DSD expansion. But, DSD settings challenge routine patient monitoring and evaluation (M&E) required to ensure quality care, risking viral suppression (VS), scarce resources, and epidemic control. Electronic medical record systems (EMRs) ensure effective patient M&E in compliance with complex guidelines, improving patient outcomes and reducing workload. Yet, despite decades of SSA EMRs investment, EMRs benefits do not extend to low resource/low infrastructure settings where the majority of DSD occurs. How to optimize collection and use of high quality M&E for DSD patient care is a critical implementation research priority. Lighthouse Trust (LT) operates two Ministry of Health (MoH) clinics in Lilongwe, Malawi, with combined >35,000 ART patients. LT’s real-time, point-of-care (POC) EMRs collects complex M&E data and provides decision-making support, ensuring adherence to integrated HIV/TB guidelines that optimize patient and program outcomes. LT’s EMRs scaled to all large MoH ART clinics. LT implements a nurse-led community-based ART program (NCAP), a DSD model to provide ART and rapid assessment to 2400 stable LT patients in the community. LT’s EMRs requires consistent power and server access. Without EMRs, NCAP providers lack embedded prompts and alerts, reducing integrated MoH ART guideline compliance. NCAP M&E is incomplete and burdensome, leaving data gaps that lessen VS monitoring and care continuity. Poor M&E limits NCAP expansion. Therefore, University of Washington’s International Training and Education Center for Health, LT, and Medic seek to leverage a proven, open-source digital health framework to design, deploy, and assess an offline-first, user-centered, battery-operated App, “Community-based ART REtention and Suppression” (CARES). Apps are faster to design, simpler to deploy, cheaper to maintain, and operate without constant connectivity or electricity. CARES brings a POC EMRs-like App to NCAP with real-time benefits for optimal, integrated patient care. CARES captures complete patient M&E data and syncs to facility EMRs, improving data quality while reducing workload. Guided by implementation science, we use a quasi-experimental, interrupted time-series design to assess NCAP patient care, pre- and post-CARES. Mixed-methods evaluate CARES effect on NCAP patient outcomes, data quality, workload, and cost. Aims: 1) Assess how CARES ensures high quality NCAP patient outcomes using RE-AIM to gauge reach, effectiveness, adoption, implementation, and maintenance; and 2) Estimate CARES cost to improve M&E using a systems perspective....