In this guide, we delved into the comprehensive architecture required to build a fitness app with social features akin to Strava. We explored the essential functional and non-functional requirements, the high-level components such as the API Gateway, Activity Service, and Feed Service, and crucial aspects like database design, scalability, security, and testing strategies. We also discussed key architectural trade-offs. To get a deeper understanding of how to architect such a complex system for performance and user engagement, listen to this to know more.