Opening the iTunes Store.If iTunes doesn't open, click the iTunes application icon in your Dock or on your Windows desktop.Progress Indicator
Opening the iBooks Store.If iBooks doesn't open, click the iBooks app in your Dock.Progress Indicator

iTunes is the world's easiest way to organize and add to your digital media collection.

We are unable to find iTunes on your computer. To buy and download Knock – unlock your Mac without a password using your iPhone and Apple Watch by Knock Software, Inc, get iTunes now.

Already have iTunes? Click I Have iTunes to open it now.

I Have iTunes Free Download
iTunes for Mac + PC

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

By Knock Software, Inc

Open iTunes to buy and download apps.


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.

iPhone Screenshot

iPhone Screenshot 1
iPhone Screenshot 2
iPhone Screenshot 3
iPhone Screenshot 4

Apple Watch

iPhone Screenshot 1
iPhone Screenshot 2

Customer Reviews

Works Perfectly

So I was a bit uneasy when buying this app because of the misguiding comments, but after much research (YouTube,Google,etc) I finally had the nerve to buy the app. And I am not disappointed. This app really works as advertised, and it works while I use other apps on my phone, which I thought it was pretty neat. The setup with almost instant, and works when my iPhone is locked. Yes, it really does, however you have to Wake up the computer first, WAIT for the circle to fill up, THEN knock. Trust me, there really isn't any lag or wait time. Maybe just a second or two. But very useful app, I recommend it to those who have very long passwords.

Doesnt work with my iPhone 6 Plus

When i purchased the app, i was using iphone 5, and it worked as perfect as advertisement. However, it was the old time, because after a long time using samsung phone, i changed to use iphone which is iphone 6 plus again. And it doesnt work any more!
It works only when i open the app, but it doesnt when i let the app run on under (even the screen is on or off). As a result, I think it doesnt automatic connect the iphone and macbook anymore, and if so, i dont think this is a creative app because its not convenient as what we wanted when we purchased.
I hope the developers of this app could fix those errors in the next version. Otherwise, no one would purchase this app anymore in the future.

Such a Shame

I really wanted to like this product, as it seemed like a great idea. The problem is if your Mac has been asleep for a while, you can “knock” on the app until your hand fell off, and it won’t do anything. Also, I found them to be VERY misleading in how they showed how this worked. They showed a guy on their website just knocking on his phone WHILE IT WAS IN HIS POCKET mind you, and the computer magically turns on. What they DON’T tell you is that while that sure looked great, you would have to take your phone out, open it, get the app open, then put it back in your pocket with the screen still on, THEN you can do that trick. Not quite as simple as just walk up to your computer, tap your phone, and your computer unlocks. They SURE presented it that way. Pretty blatantly misleading if you ask me.

Knock – unlock your Mac without a password using your iPhone and Apple Watch
View In iTunes
Offers Apple Watch App for iPhone
  • $4.99
  • Category: Utilities
  • Updated:
  • Version: 2.0.2
  • Size: 4.4 MB
  • Apple Watch: Yes
  • Language: English
  • Seller:

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, 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, iPad Pro, iPad Pro Wi-Fi + Cellular, and iPod touch.

Customer Ratings

Current Version:
All Versions: