Knock, a newly released app for both iOS and Mac, is designed to allow users to unlock their Macs via Bluetooth with an iPhone, replacing traditional password logins.

After downloading the Knock app for iOS and the accompanying app for the Mac, an iPhone can unlock a connected Mac with two knocks on the back of the iPhone. The iOS app pairs specifically with the Mac app, which creates a secure connection between the two, and the process does not require opening the Knock app.

Faster and safer than typing a password, for iOS and Mac.

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.

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.

Because it uses Low Energy Bluetooth 4.0, Knock is compatible with the iPhone 4s or newer, along with the 2011 MacBook Air or newer, the 2012 MacBook Pro or newer, the 2012 iMac or newer, the 2011 Mac mini or newer and the 2013 Mac Pro.

Knock for iOS can be downloaded from the App Store for $3.99 [Direct Link]. The accompanying Mac app can be downloaded from the Knock website for free.

Top Rated Comments

Reason077 Avatar
158 months ago
And if your iPhone breaks somehow, how do you access your mac then?
Due to the advanced security, it's impossible. You need to buy a new Mac.
Score: 33 Votes (Like | Disagree)
0160033 Avatar
158 months ago
Broken iPhone incoming.

Hey don't Knock it till you try it
Score: 28 Votes (Like | Disagree)
3bs Avatar
158 months ago
And if your iPhone breaks somehow, how do you access your mac then?

Just type in the password?
Score: 15 Votes (Like | Disagree)
Reason077 Avatar
158 months ago
The guy in the video looks like a giant douche with his silly beard. I'd like to "knock" him. In the face.
Score: 15 Votes (Like | Disagree)
unplugme71 Avatar
158 months ago
My iPhone has a cracked screen. I knocked. Cut my hand. Bleeding

Just called my lawyer..
Score: 14 Votes (Like | Disagree)
3bs Avatar
158 months ago
'Knock' iOS App Uses Bluetooth 4.0 to Replace Password Unlocking on Macs

Just make sure you remember to knock the back of your iPhone!

Unless you have a naked iPhone 4S, that is. Given how easily I've seen the backs of iPhone 4/4S break, knocking it anywhere is probably best avoided.
I think you're exaggerating. They said knock, not punch :p

Sure drops might break it but simply knocking can't possibly break the back unless there was already serious structural damage.
Score: 9 Votes (Like | Disagree)

Popular Stories

iOS 26

When Will Apple Release iOS 26.2?

Monday December 1, 2025 4:37 pm PST by
We're getting closer to the launch of the final major iOS update of the year, with Apple set to release iOS 26.2 in December. We've had three betas so far and are expecting a fourth beta or a release candidate this week, so a launch could follow as soon as next week. Past Launch Dates Apple's past iOS x.2 updates from the last few years have all happened right around the middle of the...
iPhone Pocket Short

iPhone Pocket is Now Completely Sold Out Worldwide

Tuesday November 25, 2025 7:16 am PST by
Apple recently teamed up with Japanese fashion brand ISSEY MIYAKE to create the iPhone Pocket, a limited-edition knitted accessory designed to carry an iPhone. However, it is now completely sold out in all countries where it was released. iPhone Pocket became available to order on Apple's online store starting Friday, November 14, in the United States, France, China, Italy, Japan, Singapore, ...
Sad Siri Feature

Apple AI Chief John Giannandrea Retiring After Siri Delays

Monday December 1, 2025 2:16 pm PST by
Apple AI chief John Giannandrea is stepping down from his position and retiring in spring 2026, Apple announced today. Giannandrea will serve as an advisor between now and 2026, with former Microsoft AI researcher Amar Subramanya set to take over as vice president of AI. Subramanya will report to Apple engineering chief Craig Federighi, and will lead Apple Foundation Models, ML research, and ...
Netflix Smaller 4

Netflix Kills Casting From Its Mobile App to Most Modern TVs

Monday December 1, 2025 4:36 am PST by
Netflix has quietly removed the ability to cast content from its mobile apps to most modern TVs and streaming devices, including newer Chromecast models and the Google TV Streamer. The change was first spotted by users on Reddit and confirmed in an updated Netflix support page (via Android Authority), which now states that the streaming service no longer supports casting from mobile devices...
Cyber Week Deals 2025

Best Cyber Week Apple Deals Include Big Discounts on AirPods, Apple Watch, and More

Sunday November 30, 2025 7:33 am PST by
Cyber Week is here, and you can find popular Apple products like AirPods, iPad, Apple Watch, and more at all-time low prices. In this article, the majority of the discounts will be found on Amazon. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment, which helps us keep the site running. Specifically,...
maxresdefault

iPhone Fold: Launch, Pricing, and What to Expect From Apple's Foldable

Monday December 1, 2025 3:00 am PST by
Apple is expected to launch a new foldable iPhone next year, based on multiple rumors and credible sources. The long-awaited device has been rumored for years now, but signs increasingly suggest that 2026 could indeed be the year that Apple releases its first foldable device. Subscribe to the MacRumors YouTube channel for more videos. Below, we've collated an updated set of key details that ...
studio display purple february

M5 iPad Pro Could Hint at New Studio Display Feature

Sunday November 30, 2025 10:30 am PST by
The updated specs of the M5 iPad Pro may point toward a major new feature for Apple's next-generation Studio Display expected in early 2026. Apple's latest iPad Pro debuted last month and contains one display-related change that stands out: it can now drive external monitors at up to 120Hz with Adaptive Sync. The feature should deliver lower latency, smoother motion, and fewer visual...
Touchscreen MacBook Feature

Here Are the Four MacBooks Apple Is Expected to Launch Next Year

Monday December 1, 2025 5:00 am PST by
2026 could be a bumper year for Apple's Mac lineup, with the company expected to announce as many as four separate MacBook launches. Rumors suggest Apple will court both ends of the consumer spectrum, with more affordable options for students and feature-rich premium lines for users that seek the highest specifications from a laptop. Below is a breakdown of what we're expecting over the next ...
New Intel Logo

Apple and Intel Rumored to Partner on Mac Chips Again in a New Way

Friday November 28, 2025 7:33 am PST by
While all Macs are now powered by Apple's custom-designed chips, a new rumor claims that Apple may rekindle its partnership with Intel, albeit in a new and limited way. Apple supply chain analyst Ming-Chi Kuo today said Intel is expected to begin shipping Apple's lowest-end M-series chip as early as mid-2027. Kuo said Apple plans to utilize Intel's 18A process, which is the "earliest...
iphone black friday gold

The Best Black Friday iPhone Deals Still Available

Friday November 28, 2025 6:24 am PST by
Cellular carriers have always offered big savings on the newest iPhone models during the holidays, and Black Friday 2025 sales have kicked off at AT&T, Verizon, T-Mobile, and more. Right now we're tracking notable offers on the iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air. For even more savings, keep an eye on older models during the holiday shopping season. Note: MacRumors is...