From the August Smart Locks website: “Ever forget or lose your keys? Wonder if you locked the door on your way out? Or go all the way home just to let someone in? August Smart Locks take any worry out of getting into your home. Use an app on your phone to control your door to unlock/lock, grant guest access, see who came and left, and let anyone in from anywhere. Simply attaches to your existing deadbolt on the inside of your door – your outside lock stays the same and you keep your existing keys.”

Uses a couple of AA (?) butteries that are easy to access and change. You can still use your key and lock the door manually if you need to.

PS: Sorry about the annoying sniffs. Runny nose.