BACKGROUND: Mental health mobile applications are a cost-effective and scalable answer to the world's psychiatrist shortage and limited access to care in remote areas. However, there is currently no mobile application for providing mental health interventions in Ethiopia. Therefore, this project aimed to develop and test the preliminary effectiveness and acceptability of an Android-based mobile application for mental health information, psychological self-testing, and treatment recommendation during COVID-19 and beyond. METHODS: We conducted a preliminary assessment to review experiences and demands associated with the mental health mobile apps. Object-oriented modeling and the Agile Development software development methodology were employed. Android Studio's layout editor, resource management, palette, and theme editor were used. We utilized Java as the programming language for writing application code, eXtensible Markup Language (XML) to construct the overall structure of the app, and SQLite to save data locally on the user's device. To ensure quality, tests were performed on a regular basis throughout the development process. RESULTS: The project developed an Android-based mobile app for mental health information, psychological self-testing, and treatment recommendations for COVID-19. A preliminary assessment found no existing mobile apps for mental health care. Of participants, 94.6% believed mental health apps benefit the public, patients, and healthcare professionals. However, some individuals opposed the app due to concerns about self-treatment and medication misuse. CONCLUSION: The study indicates a high demand for a mental health mobile app, but few participants fear self-treatment or drug abuse. Apps that support native languages are recommended, and nonpharmacological treatments should be used in conjunction with clinician consultation.