As far as features go, the one that stands out the most on the iPhone 5S is the Touch ID feature – an integrated fingerprint sensor located under a new sapphire home button that will scan your ‘sub-epidermal layers’ at 500ppi. You can use the Touch ID feature to either unlock your iPhone or to authenticate purchases when buying apps, movies, music in the App Store and iTunes store.
Theoretically, Apple allows us to register up to 5 fingerprints, but thanks to a bug or loophole or whatever you want to call it, you can register up to 25 unique fingerprints. Jump over the break to check out how to do it..