Introduction Mobile applications (apps) for exercise prescription may enhance communication between healthcare providers and patients while addressing common barriers to exercise among people with osteoarthritis. However, little is known about preferences and barriers to the use of mobile apps by physical therapists or people aging with osteoarthritis. Therefore, we aimed to examine physical therapist and patient perspectives on mobile apps to support physical therapist-prescribed home exercise for people with osteoarthritis. Methods Eighteen physical therapists and 17 individuals with a history of physical therapy for osteoarthritis participated in the study. Focus groups (n = 6, three each with physical therapists and patients) were conducted to gather perspectives on three commercially available mobile apps designed for physical therapy exercise prescription. Semi-structured questions assessed feature preferences, ease of use, exercise completion support, clinical feasibility, and potential barriers and facilitators to using the apps. Recordings of the focus groups were transcribed verbatim. The study team iteratively coded transcripts using thematic analysis. Results Perspectives of patients and physical therapistsintersected but differed on the mobile apps. All patients preferred video exercise prescription over traditional methods and bothpatients and therapistspredicted challenges and opportunities with mobile communication. Four themes emerged: accountability, data-driven, communication boost, and duality of technology. Facilitators of home exercise through mobile apps included exercise tracking, feedback loop, personalization, and the potential for reduced in-person visits. Barriers included technological challenges, complex interface design, lack of universal applicability, and security concerns. Conclusion Mobile app technology has the potential to support exercise adherence for people with osteoarthritis. However, patients' and therapists' perspectives differ and highlight numerous challenges that limit the universal clinical adoption of this technology. While physical therapists acknowledged the potential to improve the rehabilitation experience with mobile apps, there was concern about reimbursement and time constraints in the current fee-for-service environment.