Apple unveiled a hotly anticipated feature in the iPhone 5s on Tuesday, Touch ID. This is a fingerprint-based authentication technology that you can use to unlock your iPhone and confirm iTunes purchases, a significant step closer to an Apple-branded "mobile payment" solution.
Apple announced the feature during its "This should brighten everyone's day" media event in Cupertino, CA.
Touch ID Setup
Touch ID works through a new capacitive sensor Apple is embedding in the iPhone 5s's home button, It scans sub-epidermal skin layers, has 360 degree readability, and scans at a resolution of 500 pixels per inch. It's 170 microns thin. It has a stainless steel detection ring around the home button, and it's protected by a sapphire crystal.
Apple's Exploded View of the Touch ID Sensor on iPhone 5s
iPhone 5s customers will be able to use the feature to unlock their device, and each iPhone 5s will be able to recognize multiple fingerprints. That should be useful for folks who want their family members make phone calls with their device.
It will also authenticate iTunes purchases. This means that when you buy an app, a song, a TV show, a movie, or a book, you can simply use your finger to approve the purchase.
According to Apple, "All fingerprint information is encrypted and stored securely in the Secure Enclave inside the A7 chip on the iPhone 5s; it’s never stored on Apple servers or backed up to iCloud."
Apple didn't say this, but this is most likely a first step towards Apple offering a mobile payment solution based on our iTunes accounts. Apple has long been rumored to be working on such a system, and this is assuredly the first step down that path.
We should also note that Touch ID is the result, in part, of technology purchased when Apple acquired AuthenTec in 2012 for US$365 million.
Apple has more on Touch ID in a video posted to the iPhone 5s site. It's the second half of the video, the part narrated by Apple SVP Dan Riccio.
[Update: This article was updated with additional information and images.]