Develop an iOS Core Motion / GPS tracking, recording and social application

We are looking to appoint an app developer to develop an iOS iPhone application which will measure, track, record and compare core motion / gps data. The developer must be able to begin work immediately. The multilingual sports based solution will use core motion and gps data to record and monitor activities of the user's iPhone and be integrated to google maps API for visualisation. The solution (which must have an in-app purchase to unlock content / remove limitations) will store data from the sport locally on the app as well as send to the cloud database for central analysis. The application will compare a range of user's performance characteristics against others (following social media login) from the central cloud database and present back to the user on the app including other users' locations (near real-time). Where data is unavailable ie no service, the application will read the last available data. The app will also read from one / two other simple APIs. Key Skills: We are looking for a developer who has experience with: - Core Motion Experience - GPS Tracking Experience - Integration to databases / APIs within the app - Google Maps API - Reading and writing data to a database - Social media login / integration Initial launch will be one language (English). Second launch will be multi-lingual. What we will provide - Functional specifications including UI components (SketchApp based) - Cloud hosting and domains - We will launch the application What you will provide - Application UI review and freshen up using your best practice - Application development with warranty (to cover bugs) including databases Timelines Suppliers must be able to begin immediately, and have initial demo solutions ready within 3/4 weeks Credentials Suppliers must provide valid example reference applications that demonstrate core motion, gps, google maps work