Apex Cross-Platform Mobile Workout & Coaching App
A high-performance React Native iOS and Android app featuring offline workout logging, biometric health sync, and live session streaming.
Problem
Gym environments frequently have poor cellular reception. The app needed 100% offline logging for sets, reps, and workout timers with automatic conflict-free synchronization upon reconnecting.
Approach
Apex Mobile brings personal coaching and custom workout progression directly to members' pockets. Synchronizes seamlessly with Apple HealthKit and Google Fit while caching exercises for offline gym usage. Engineered with React Native and WatermelonDB for local SQLite persistence. Built an idempotent sync protocol with Node.js / Express and MongoDB. Integrated Apple HealthKit and Google Fit APIs. Built in collaboration with A. S. M. Asif Islam (asmasif.com), who led the engagement; I worked on the build alongside him.
Impact
Offline-First Local SQLite Engine: Members can log full workouts in basement gym facilities with zero internet connection. Apple HealthKit & Google Fit Sync: Automated resting heart rate, calorie burn, and step count telemetry ingestion. Interactive Video Exercise Library: High-definition cached video demonstrations with form guidance and angle analysis. Push Notification Reminders: Customized workout consistency nudges powered by Firebase Cloud Messaging (FCM).
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