Existing iOS app enhancement & versions

1. To make a few enhancements on the existing iOS (iPhone, iPad) app including: a. Correcting a main bug on the main thread (latency bug) b. Adding accelerometer on and off switch on the info/settings view c. Enhancing application to iOS app switching (multitasking) d. Ensuring that Game center is a user option on the the info/settings view and not triggered from the AppDelegate 2. To create multiple versions from the full app for iPhone and iPad a. Create targets for free iPhone app, free iPad app, paid iPhone, paid iPad Timeframe for delivery: I need to have this up and running within 1 week.