One of the neatest features added to WatchOS 3 and MacOS Sierra is the ability to unlock your Mac with your watch. Apple uses several new technologies to do this that use high encryption, and data speed measurements to determine if it is ok to unlock your Mac. The cool thing about this is that it is easy to set up. Here’s how you do it.

Prerequisites

1. Your Mac must at least be a 2013 model Mac for this feature to work.
2. You must first set up two-factor authentication with your iCloud account. If you haven’t done so, the Mac will walk you through this process.
3. You must make sure you are not using your iCloud password to log into your Mac. This will require you to set a different login password for your user account than what is used for your iCloud account.

Setting up Unlock from Apple Watch

1. Open System Preferences on the Mac
2. Find Security and Privacy
3. Find the check box that says, “Allow your Apple Watch to unlock this Mac”
4. Follow any instructions given to enable two factor authentication or to set a non-iCloud Password

That’s it! Now, when you go to unlock your Mac, you should just have to wait for your watch to unlock the computer. If for some reason the process does not work, or both devices can’t find each other, you will still need to type your password.