You can turn on the “Show Battery Percentage” function within the Tapplock App (in the Setting menu) to check battery percentage once connected.
To view an updated battery percentage of your Tapplock, you will need to have the lock connected via Bluetooth and the Tapplock App
As an added precaution, if the remaining battery is at 30% or below, the status indicator will show a blinking red light to remind you of charging after you turn on the lock.