There are some question which are related to this,. but getting the exact answer:
Lock-down iPhone/iPod/iPad so it can only run one app
Recently iOS 6 is introdu
For this you have to do following..
Apple don't encourage accessing there private api's specially when it comes for App Store, if you accessed the private api's at the time of application review on App Store they will reject the app giving you a message of "accessing a private api".