BACKGROUND: Medical culture refers to institutional attitudes toward technology usage, innovation, teamwork, and evidence-based practices. Hospitals with strong innovation cultures promote mobile app use, while traditional settings may resist change, relying on conventional methods. Medical culture significantly influences the usage of technology in health care, including mobile health (mHealth) applications, which have the potential to enhance patient care in physical therapy settings. Understanding the role of medical culture and other factors such as app usability and workplace setting in shaping the usage and perceived effectiveness of mobile apps is essential for promoting their integration into clinical practice. OBJECTIVE: The study aimed to assess how medical culture influences health care professionals' usage of mobile apps in clinical settings, particularly in physical therapy interventions, and to examine the relationship between the perceived effectiveness of mobile apps and cultural attitudes toward technology in health care teams. METHODS: This cross-sectional study was conducted between April 2023 and March 2024 at a tertiary care hospital specializing in rehabilitation and physical therapy. A total of 456 health care professionals, including physical therapists and rehabilitation specialists, were surveyed. Medical culture was measured using a composite scale, while mobile app usage and perceived effectiveness were assessed through structured questionnaires. RESULTS: Medical culture was strongly associated with mobile app usage frequency (r=0.54, P=.01), and multiple linear regression analysis showed that medical culture significantly predicted app usage (β=.45, P=.002). App usability, in terms of ease of use (β=.37, P=.008) and patient engagement features (β=.28, P=.02), also contributed to the perceived effectiveness of mobile apps. Hospitals showed higher usage and perceived effectiveness than private practices and rehabilitation centers. Years of experience (β=.32, P=.01) and app usage frequency (β=.45, P=.01) were additional significant predictors. CONCLUSIONS: This study highlights the critical role of medical culture in promoting the usage and perceived effectiveness of mobile apps in physical therapy. Positive cultural attitudes toward technology, combined with user-friendly app designs, can enhance the integration of mHealth tools in clinical settings. These findings underscore the importance of fostering an innovative medical culture and supporting the development of usable, patient-centered applications to optimize patient care.