Got a tip for us? Share it...

'Knock' iOS App Uses Bluetooth 4.0 to Replace Password Unlocking on Macs

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

(View all)

Posted: 11 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.
Rating: 33 Votes
Posted: 11 months ago

Broken iPhone incoming.


Hey don't Knock it till you try it
Rating: 28 Votes
Posted: 11 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.
Rating: 15 Votes
Posted: 11 months ago

And if your iPhone breaks somehow, how do you access your mac then?


Just type in the password?
Rating: 15 Votes
Posted: 11 months ago
My iPhone has a cracked screen. I knocked. Cut my hand. Bleeding

Just called my lawyer..
Rating: 14 Votes
Posted: 11 months ago
Watching him knock on the glass of that phone just made me cringe.
Rating: 9 Votes
Posted: 11 months ago

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.
Rating: 9 Votes
Posted: 11 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.


Honestly, I expected the beard to magically disappear in sync with the ease of unlocking the computer. I was shocked to see his beard intact at the end.
Rating: 8 Votes
Posted: 11 months ago
Broken iPhone incoming.
Rating: 7 Votes
Posted: 11 months ago
You have to first wake up your Mac!!

You have to manually touch a key to wake your Mac up before knocking on the iPhone. It simply doesn't wake on its own due to your proximity, like they make it seem in the video. When he comes over from behind the pillar they screen jump to the mac being on so you don't see him having to wake it up.

My experience with iPhone 5s and rMBP:

When you walk up to the computer you have to press a key to wake it up, then a green light circles your icon similarly to the light around the Siri microphone. This is when it then begins to contact your iPhone; once the light goes solid green then can you knock on your iPhone... This can take up to 6 seconds... not a long time but since I have to touch my computer anyways I then just have to sit there and not try and type in a password.

The knock pattern has to be have a fairly specific knock-knock pattern, too slow or too fast will result in a decline.

The Mac app simply enters your password into the field to unlock for those of you wondering about that.

I wish it wasn't $4, good idea but make it wake up the Mac so whenever I reach it to sit down it is already for a knock or I can knock as I approach. I bought the Keycard proximity unlock app that does a similar thing. It appears they are all a bit lagging in speed and make themselves more inconvenient than anything else.

I read the reviews before I bought and no one clarified this wake issue so I hope I helped someone..
Rating: 7 Votes

[ Read All Comments ]