Some folks digging around the developer version of iOS 7 beta 4 have uncovered a Biometric Kit which when paired with the fact that Apple purchased semiconductor-based Authentec last Summer for $356 million, then it is likely that Apple might include a fingerprint scanner for added security and access control in upcoming iOS devices.
Authentec makes fingerprint sensor chips used in personal computers and mobile devices. More than just access control, Authentec can add functionality to the home button of most iOS devices by making them more accurate cursors as well as access specific functions or apps upon verification.
Source: AppleInsider