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Knock – unlock your Mac without a password using your iPhone and Apple Watch

By Knock Software, Inc

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Knock and Apple Watch: a match made in heaven. Knock 2.0 makes unlocking your Mac faster and more secure than ever.

You keep your iPhone with you all the time. Now you can use it as a password. You never even have to open the app— just knock on your phone twice, even when it’s in your pocket, and you're in. And if you have an Apple Watch, you can unlock your Mac right from your wrist.

Using Knock won't drain your iPhone's battery, even if you use it all day every day. Knock securely communicates with your Mac using Bluetooth Low Energy, a new technology that draws very little power.


Have a question? Email us at and we'll get back to you within a day.

What's New in Version 2.0.2

- Fixes a bug that could cause Knock to fail to connect when your Mac is locked.


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Customer Reviews

Great app but has delays in opening

This is a really great app and I like using it a lot as it allows me to have a secure password on my macbook as well as have the screensaver programmed to lock the computer after a short while.

The only problem which I think isn’t an app problem but more of a bluetooth problem is that when you are away from the computer for a while and return it takes maybe 30 seconds for the app to sense the macbook is requesting an unlock. I think this is the time the bluetooth takes to connect because if i lock my computer again then unlock it the phone responds instantly.

If I’m close to my machine then the request to unlock comes to the iphone instantly and its a real time saver.

It would be cooler if it worked with fingerprint recognition but the knock is pretty cool idea although you do need to knock the phone pretty hard.

It’s Ok. A gimmick really.

It’s cool when you have unlocked it once or twice, but it’s hard to find the opportunity in your day to day. You often find that your hands are already on the keyboard by the time the phone buzzes. What’s worse is that when your bluetooth connection disconnects, because maybe you walked away from you machine, it takes too long to reconnect.

All this being said it has been built and designed really well and the developers deserver a pat on the back for a really good quality App here.

Lovely idea - not ready for real world yet

Fantastic presentation. Beautiful design and it does work - just not all the time. Sometimes the phone responds to knock, other times the watch prompts for input. Both with delay. Sometimes neither - so I just log in as usual. Sadly it doesn’t live up to the considerable and very attractive presentation on the website. One to watch certainly and for sheer marketing prowess I don’t begrudge the price of admission. As a product though doesn’t live up to the promise yet.

Knock – unlock your Mac without a password using your iPhone and Apple Watch
View in iTunes
Offers Apple Watch App for iPhone
  • £5.99
  • Category: Utilities
  • Updated:
  • Version: 2.0.2
  • Size: 12.0 MB
  • Apple Watch: Yes
  • Language: English
  • Developer:

Compatibility: Requires iOS 7.0 or later. Compatible with iPhone 4s, iPhone 5, iPhone 5c, iPhone 5s, iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7, iPhone 7 Plus, iPad Wi-Fi (3rd generation), iPad Wi‑Fi + Cellular (3rd generation), iPad Wi-Fi (4th generation), iPad Wi-Fi + Cellular (4th generation), iPad mini Wi-Fi, iPad mini Wi-Fi + Cellular, iPad Air, iPad Air Wi-Fi + Cellular, iPad mini 2, iPad mini 2 Wi-Fi + Cellular, iPad Air 2, iPad Air 2 Wi-Fi + Cellular, iPad mini 3, iPad mini 3 Wi-Fi + Cellular, iPad mini 4, iPad mini 4 Wi-Fi + Cellular, 12.9-inch iPad Pro, 12.9-inch iPad Pro Wi-Fi + Cellular, 9.7-inch iPad Pro, 9.7-inch iPad Pro Wi-Fi + Cellular, iPad Wi-Fi (5th generation), iPad Wi-Fi + Cellular (5th generation), 12.9-inch iPad Pro (2nd generation), 12.9-inch iPad Pro Wi‑Fi + Cellular (2nd generation), 10.5-inch iPad Pro, 10.5-inch iPad Pro Wi‑Fi + Cellular and iPod touch.

Customer Ratings

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