
Once you've unlocked your Apple Watch, wrist detection can keep it unlocked for as long as it maintains skin contact.
As security systems go, wrist detection is clever: It lets you have the convenience of accessing your
Apple Watch without having to continually re-enter your passcode or password, but provides enough security to protect your data, including
Apple Pay credentials under normal circumstances. In that way it's similar to
Touch ID, which can unlock your iPhone or iPad based on your fingerprint.
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