Healthcare professionals established An-EsO to fulfill their pharmacovigilance activity needs. The ADR reports in Indonesia remain relatively low, compared to other countries worldwide. Our prior research findings suggest that the inadequate reporting by healthcare professionals is attributable to time constraints, heavy workloads, challenges in accessing reporting forms, and uncertainty on the causation of reactions by the drug being used. Consequently, we created an application, namely "An-ESO," to fulfill that requirement. The study commences with the assessment of user requirements leading to the usability test. The An-ESO app is anticipated to assist healthcare professionals in monitoring, documenting, evaluating, and reporting ADRs on a unified platform. It is anticipated that this will enhance both the volume and the quality of ADR report data on a national level. In addition, this application is also equipped with tools and educational/informational materials needed by healthcare professionals to support their daily clinical practice activities.