Here is a Bluetooth deadbolt that turns your existing lock smart. The Level Bolt can be installed with a screwdriver and works with iOS and Android devices. It has an “invisible” design and can be controlled with the Level app. You can also continue using your existing key.
The Bolt has a 6-stage stainless steel gearbox and can run on a CR2 battery for over a year. You can find out more about it here.