Knock

Knock 2.2

Free
Faster, safer way to sign in. You keep your iPhone with you all the time. Now you can use it as a password.
4.7  (58 votes)
2.2.1 (See all)

Knock is a faster, safer way to sign in. You keep your iPhone with you all the time. Now you can use it as a password. You never have to open the app -- just knock on your phone twice, even when it's in your pocket, and you're in.

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