Cross Platform GPS History Tracker

I need a complete solution that records a phone’s location history with high-accuracy GPS on both Android and iOS. Each device should log points with timestamp, latitude, longitude, speed, and battery level, then sync them to a secure cloud back-end in near real time (offline buffering when the signal drops is a must).

I want to view the data two ways: inside the mobile app itself (simple map timeline per day) and through a web dashboard where I can filter by date, export to CSV/KML, and see heat-maps or breadcrumbs for each selected device. Basic account management and role-based access will keep the data private.

You are free to choose the stack—Firebase, AWS Amplify, Supabase, or another cloud service—so long as it scales and keeps costs predictable. If you plan to use Flutter, React Native, or Kotlin/Swift with a shared codebase, let me know; cross-platform speed matters.

Deliverables:
• Android app (Play-ready APK/AAB)
• iOS app (App Store–ready IPA)
• Responsive web dashboard with login
• Documented back-end with REST/GraphQL endpoints
• Setup guide and brief hand-over call

Acceptance Criteria:
• GPS accuracy consistently under 10 m in open sky tests
• Seamless data sync within 30 s of collection when online
• Dashboard loads a 30-day history of 10 000 points in under 5 s
• Code passes a security review for unauthorized data access

If parts of this scope need clarification, mention them early so we can lock requirements and timelines.