In a Beta of iOS 15.4, one of the new features is FaceID that works while wearing a mask. Apple says the iPhone can recognize unique features around the eyes to authenticate, and that you must look at your iPhone to use Face ID while wearing a mask.
Apple says that Face ID is most accurate when it’s set up for full face recognition only. So this implies that the feature to Use FaceID With a Mask is less secure. How much less secure?
Security, we think of it like it’s a binary state, but it’s really a threshold.
— Renee Richie, speaking on Mac break weekly 803.
Various things land at different places on this continuum of security. If full-face Face ID is more secure than masked Face ID, both are still more secure than a 6-digit pin. It’s very easy to shoulder-surf to see what someone is using for a 6-digit pin for their phone. If you’re wearing a mask in a place where there are other people, this is a nice step forward in both security and convenience.
It’s a Beta now, but that likely means it will be generally available in the next couple months or so.