Nice interaction but slow and the password prompt needs to be visible on the screen for it to work

Not reliable at ALL. It works a few times then you have to setup again for it to start working. Furthermore being really really slow to activate I actually type the password ALL THE TIME so I end up never using it. Waste of money.

Interaction is nice, better than just proximity as you can choose to unlock your mac. The problem is that it cannot unlock from screen saver nor from a sleeping mac. The video posted on the site makes you think otherwise. Furthermore it needs a few seconds to become active, so in actual fact is SLOWER than inserting a moderately long password.

cloudpower about Knock – unlock your Mac without a password using your iPhone and Apple Watch, v1.0.1