BACKGROUND: The number of mobile apps tailored for people living with mental health conditions has increased tremendously. However, the majority of the existing apps are not evidence-based and are being developed by teams without mental health expertise. OBJECTIVE: We aimed to explore psychiatrists' perceptions of what they and their patients need in a mental health app and eventually inform the design of future mobile apps in this area. METHODS: Semi-structured interviews were conducted with psychiatrists (= 18) from three European countries: Austria, the Czech Republic, and Slovakia. Content analysis using inductive and deductive coding was used to analyze the interviews. RESULTS: Four major themes were deductively identified: current system, gaps in the current system, recommendations for a mobile app, and promoting app use. Psychiatrists provided a comprehensive list of app features they suggested would be helpful. Of particular importance seemed to be enabling patients to self-monitor various aspects of their lives and including an emergency plan. Participants also emphasized that the app should be positive and motivating for patients to use, with some suggesting that users be able to communicate with other users for support. Within the theme of "current system," a common topic was the current shortage of psychiatrists and the feelings of time pressure amongst existing psychiatrists. CONCLUSIONS: The results of this study can be used by software developers to inform future designs of mental health mobile apps, which will hopefully translate to a greater availability of evidence-based apps that address clinical needs.