There’s one big conceptual difference between Face ID and its predecessor, Touch ID. With a fingerprint, you have to explicitly touch the home button to confirm an action. When unlocking a password-protected app, or unlocking the iPhone itself, it’s hard to do it unintentionally. But what about buying an app? The old Touch ID way is to tap the buy button, and then use your fingerprint to confirm the purchase. What happens with Face ID? How do you cancel a purchase after tapping buy? Do you look away? Close your eyes?
No. It’s much simpler than that, although much less discoverable than touching a fingerprint scanner.
Face ID purchases in action
In this video posted by reviewer Adrian Weckler on Twitter, you see Face ID purchases in action. To make a purchase, you tap the app’s price (labeled Get for free apps), and the familiar iOS 11 sheet slides up with the app’s details, and a Cancel button. To abandon the purchase, tap Cancel. To go ahead with the transaction, you now have to double-click the power button on the top right side of the handset. This initiates the Face ID scan, and installs the app.
Just like Apple Pay
This is exactly the same method used to make an Apple Pay purchase in a store. To do that, you double-click on the side button, then let the iPhone X authenticate you using Face ID. After authentication, you can wave your iPhone over the credit card terminal to pay, just like with other iPhones right now.
This method is less intuitive than using your fingerprint to authenticate, if only because it is less discoverable. But as you see in the video, the iPhone X prompts the user with a little label at the edge of the screen, next to the power button. And once you get used to it, the new method may actually make more sense, because it is more consistent.
Right now an Apple Pay purchase, and an App Store purchase use different mechanisms. One is uses double-tap on the home button, the other uses an on-screen prompt to initiate a finger scan. With iPhone X, both transactions work the same way.
It’s going to take a little while to get used to all the new gestures now that the home button has gone, but the convenience of Face ID — especially when it eventually comes to the iPad — will be worth it.