iPhone Duo uses Touch ID rather than Face ID, marking the return of fingerprint authentication to Apple’s flagship iPhone lineup.
The Touch ID fingerprint sensor is built directly into iPhone Duo’s side button. It can be used to unlock the device, authenticate purchases and approve Apple Pay transactions without opening the phone.
Despite having cameras on both the outer and inner displays, Apple does not include Face ID on iPhone Duo. The inner display instead features an under-display FaceTime camera that stays hidden when it is not being used.
Putting Touch ID in the side button allows the same authentication method to work whether iPhone Duo is folded or unfolded. Users can simply place a registered finger on the side button while holding the device.
The arrangement is similar in principle to the Touch ID implementation Apple has used on several iPad models, although its appearance on iPhone Duo is notable after years of Face ID being standard on Apple’s premium iPhones.
iPhone Duo will be available beginning October 23 following preorders on October 16.