Introduction: There has been a sharp increase in the use of digital health interventions in global health, particularly mobile health applications, in recent years. The extreme shortage of health care providers trained in mental health screening and intervention in low- and middle-income countries raises questions about the applicability of mobile applications to deliver these services due to their accessibility and availability. This exploratory paper describes the development and feasibility assessment of a mobile screening application for the detection of mental disorders among adolescents in Zambia and South Africa. Methods: Eighty-two health care workers (HCW) working in primary care evaluated the acceptability and practicality of the mobile screening application after receiving brief training. The evaluation included questions from the Mobile Application Rating Scale (MARS) as well as open-ended questions. Results: The acceptability of the screening app was high and study participants were positive about using the app in routine care. Problems with internet connectivity, and time and staff constraints were perceived as the main barriers to regular use. Conclusion: HCW in primary care were able and willing to use a mobile screening app for the detection of mental health problems among treatment-seeking adolescents. Implementation in clinical practice needs to be further evaluated. © 2022 Taylor & Francis Group, LLC.