Apple explains how the iPhone 5S will store your fingerprints

Are you keen on getting your hands on an iPhone 5S but hesitant about giving Apple access to everything from your email address to credit card details and now your fingerprints? You’re not alone.

Since Apple announced its new Touch ID feature, which allows iFans to unlock their device simply by resting their fingertip on the redesigned home button, there have been questions raised about how secure that biometric data will be and where the information will be stored, especially in light of Apple’s reported involvement in the PRISM programme. While it has joined the ranks of others from Google to Facebook in denying that it allows the US government direct access to its servers, its latest attempt to boost the security of its devices has been met with mixed responses. While you won’t have to remember or waste time entering your password, Touch ID also requires quite a serious form of personal information to function.

For its part, Apple has made the effort to stress the system’s security from its onstage announcement at the iPhone 5S launch to its promo videos. It says that the fingerprint data is encrypted and stored inside the iPhone 5S’ new A7 chip, where it is only accessible by the Touch ID sensor, not the rest of the phone’s components. The company says the fingerprint is never available to other software on the device or third-party apps, and it isn’t stored on Apple servers or backed up to iCloud. So your fingerprint information will be safe if someone hacks your Apple account — but what if they get hold of your phone?

Speaking to the Wall Street Journal, an Apple spokesperson confirmed that the device will not store an image of its owner’s fingerprint, just the data from the scanner. This means that if someone stole your phone and managed to decrypt the data, they would also have to reverse engineer the actual image of your fingerprint from the digital signature stored in the chip. Apple says it also requires users to setup a backup password, which will have to be entered if the phone has been restarted or hasn’t been unlocked for more than 48 hours, which could help delay hackers trying to get around the fingerprint system.

All that may help make your phone more secure, especially considering the inclusion of an additional level of security through the passcode option. If the most commonly used passwords are anything to go by, your unique fingerprint may be a better option than defaults like “1234” anyway. Still, there are some downsides to fingerprint scanner — Apple says that it may have problems reading fingers which are scarred, or covered in anything from moisturiser to water.