Mobvoi announced that it is launching sleep tracking for its TicWatch Pro smartwatches today, as well as an Android app called TicSleep to track sleep data from the watch. Mobvoi says that the TicWatch Pro’s sleep tracking features work automatically, so you should be able to just go to bed with the watch on and it will start tracking.

The Wear OS smartwatch will track your sleep cycles and heart rate, according to Mobvoi, and can wake you up with a customizable vibration that activates when you’re “in a state of light sleep.” You’ll also be able to view your sleep data history.

The one thing we don’t know is how much this feature will affect battery life, which Mobvoi says is 2-5 days. Hopefully, it doesn’t impact that too much.

Mobvoi says the feature will be compatible with watches in its TicWatch Pro line, starting with the TicWatch Pro BT and TicWatch Pro 4G/LTE. The original TicWatch Pro went on sale in July 2018.