The EFDA-AEFI app, an Android application developed for the COVID-19 vaccination campaign in Ethiopia, facilitates the reporting of Adverse Events Following Immunization (AEFI). It allows health workers and vaccinated individuals to submit reports, thereby enabling the Ethiopian Food and Drug Authority (EFDA) to monitor these events in real time. Designed for use across the entire vaccination supply chain, the app enhances oversight of vaccination-related adverse events, focusing on vaccination and immunization health areas.