I’ve tried using various third-party apps to unlock my iMac using my Apple Watch (MacID, Knock, etc.) but I never found a solution that worked consistently and that just got out of the way. But Apple’s official unlock with Apple Watch feature — new in MacOS Sierra — works GREAT (though I did run into a minor glitch during setup which I’ll tell you how to fix below).
For me, unlocking my Mac with this new feature usually takes about two seconds (but occasionally it can take closer to four). That’s on a fully-maxed 2015 27″ Retina iMac. Instead of a password box on the lock screen you’ll see your user image with a message that says unlocking with Apple Watch. On your Watch you’ll also get a Mac Unlocked notification.
All said getting the settings right took about three minutes from start to finish.
To setup your Mac to unlock with your Apple Watch you just need to do two things: 1.) setup and enable two-factor authentication (if you haven’t already) and then check the appropriate box in your Mac’s security settings.
1.) Enabling Two-Factor Authentication
To setup or enable two-factor authentication I would recommend doing everything from within your Mac’s settings (though you can do it elsewhere). Click the Apple icon in the top left corner of your screen, click iCloud and then ...