Face ID permits a single user to register their face, as opposed to Touch ID which supports up to five different fingerprints. Apple’s chief of software engineering explains why.

In an alleged response to an email inquiry from a customer, shared on Reddit, Federighi explains that Touch ID was never intended for multiple users anyway.

Here’s Federighi’s response in full:

Currently, we’re focusing Face ID on single-user authentication. Even Touch ID’s multi-finger support was really intended to enable a single iPhone owner to unlock the device with a finger and thumb on both hands, not to enable multi-user authentication.

Apple’s Senior Vice President of Software Engineering wrapped up by noting that Apple will keep feedback like that in mind “as we consider our plans to evolve Face ID in the future.”

MacRumors notes that the email is probably authentic given that the Reddit user who shared it has a good reputation and history on the website. “However, we are still waiting to receive full headers of the email to verify its origins,” notes the publication.

It’s thought that Face ID’s single-user design stems from it being a brand new biometric feature that Apple wants to get right before introducing multi-face support. Another speculation has it that matching the user’s face against multiple registered faces would slow down response time noticeably due to the sheer amount of processing power required for 3D facial recognition.

Overall, I’m not concerned because I’m sure Apple will iterate Face ID so I’m expecting it to support multiple faces in the future. That said, however, I can see how this is annoying those who may want to share their device easily with trusted family members or friends.

Is Face ID’s single-user design something you miss versus Touch ID’s ability to match agains multiple stored fingerprints? Let us know in the comments!

  • Greg Warren

    I miss it, but it’s not a deal breaker. I’m sure they’ll eventually add it but for now it’s fine the way it is. I’m a little surprised that they said Touch ID was only really intended to support one person though. I don’t remember seeing that documented anywhere and it always felt like it was a nice addition being able to support multiple users

    • Darkingz

      He mentions that the reason is that TouchID was to be used with multiple fingers, probably in the case that you have a wet thumb but a workable pointer finger or pinky. You have 8 fingers and 2 thumbs after all. Or if there is something wrong with your hand. Unintended use cases (like registering multiple people) are just exploiting how the system works really.

  • malhal

    The safari passwords feature is single user too. It’s in their interest to keep everything single user, can sell more devices that way. The exception is the iPad which is only multi-user for education – they had to compromise to get the contracts.

  • :D

    Yeah iPhones are designed to be for single users – that’s why you can only log into one icloud account at a time.

  • Its somthing that keeps me away from buying an iPhone X. I used to administrate my wifes iPhone, and used TouchID to instaed of a long password. With Faceid I have to enter the password to get access to the phone, thats annoying.