Right now the Apple Watch can sort of identify its user via skin contact. Basically as long as you keep the watch on your wrist and can authenticate yourself on the watch, the device will automatically assume that you are the owner as long as the watch remains on your hand. This is also how Apple verifies users when using the Apple Watch to make payments.
It’s not quite the same as using Touch ID which relies on fingerprints, but since embedded a fingerprint sensor into the device isn’t quite practical in terms of size, what else can Apple do? According to a patent discovered by AppleInsider, it seems that Apple could be considering using vein patterns as a means of identifying users.
The patent describes how a pulse oximeter could be used to identify biometric characteristics of a user’s vasculature, thus ensuring that the wearer of the watch is who they say they are. By introducing such a feature, it helps Apple reduce the reliance of the Apple Watch on the iPhone, something that users have been asking for.
The idea of using veins as a means of identification isn’t new. Recently at CEATEC 2016 in Japan, Fujitsu showed off a palm vein scanning technology that authenticated users when it came to making mobile payments. However given that this is only a patent, there’s no telling if Apple plans on implementing it into future Apple Watch devices.