The current method that the Apple Watch uses to identify the wearer and to help authenticate Apple Pay payments is through a passcode system, where as long as the watch is on the wrist of the user and they entered the correct passcode, it’ll remain authenticated until the watch is taken off. After that the process needs to be repeated again.
Is this the most secure method? Probably not, but it works. However it seems that in the future Apple could ensure that the Apple Watch is more secure at identifying its user. A report from Patently Apple revealed a patent from Apple where it seems that the company could embed a biometric sensor into the band of the Apple Watch which will then capture the skin texture of the wearer.
What this means is that in the event that the watch is taken off and put back on, the watch can identify if the user is who they say they are through the skin texture. It might also rely on the use of an IR thermal image sensor where it will attempt to identify the cracks and creases in our skins to help make these textures and patterns more unique.
Now we’re not sure if skin texture is a viable biometric security option, especially with vein-based authentication having recently been beaten, but it is an interesting idea all the same. Whether or not Apple will go through with its development remains to be seen, as is usually the case with most patents.