Knock. To Unlock.

Knock knock.

Who's there? Your iPhone, that's who. Why? To unlock your Mac.

We all hate having to deal with security because security and convenience just don't always seem to play well together. Thankfully there are many things out there to help them get along. Things like 1Password (which has a smashing new version out for Mac, and is also a major contributor to my lack of writing here last month). Then there is the new kid on the block, Touch ID.

I've used the demo of Touch ID on an iPhone 5s at the Apple Store. It's pretty rad. I can't wait to have it next Fall (I skip the 's' generations), and I was hoping it would come to the new iPads announced a couple weeks ago. And someday I hope it comes to a portable Mac so I can stop typing in a password to login.

But until then we'll have to use creativity, and that is where Knock comes in. Knock is a pair of apps, one for your Mac, one for your iPhone. Together, they create a super duper secure link over Bluetooth 4 Low Energy.

When you wake up your Mac, it checks to see if the iPhone is close by. If it is, a green circle pusles around your avatar on the standard OS X login screen. Then, your just give your iPhone a quick knock-knock, like you're knocking on someone's door. Magically, your Mac unlocks.

The Mac app runs as a menubar utility, easily tucked away by my good friend Bartender. The iOS app just needs to hang out on your iPhone, and doesn't even need to be running. During setup you give it special permission to monitor Bluetooth and CoreLocation so it can detect the Mac and its proximity.

The best part is your iPhone doesn't even need to be unlocked. You can leave it in your pocket and give it a gentle double-tap to unlock the Mac.

I'm really impressed by Knock, and it will be indispensible not only at coffee shops, but around the house, too, as my Mac tends to fall lock down while I step away to AeroPress some coffee.

Knock is a $3.99 iOS app and the Mac app is free on their website.