With using the newer Bluetooth LE technology, it ensures that your Mac will be unlocked as soon as you knock on your iPhone. It’s as prompt and responsive as you’d expect from a paid app.
Now the question is, can your mobile phone become a replacement for manually typing in a password? Possibly no, but this paid app is well worth a try, especially if you like to keep your phone in proximity. To know more about it and download this app, head on over to its iTunes page. Source – Knock