Fingerprint phone unlock behaviour is inconsistent depending on wether the screen is on or off at the time of unlock. This results in one not being able to unlock the phone from the first attempt.
When the screen is off one has to apply finger to the fingerprint sensor (which is integrated into the power on/off button as we know) and press the button. This always works as intended.
However, if before you unlock you turn on the screen by doing either of the following:
and then try to unlock the phone like you used to, this is what happens:
When finger is applied to the sensor without pressing, the phone quickly unlocks. You continue to press the button as you've used to and the phone locks itself because the button now acts as a 'lock' button. It can take two or more attempts before one can understand what's going on. User has to carefully monitor the screen state, in one state user has to press the button to unlock, in the other state just apply the finger.
Current behaviour: Fingreprint unlock procedure is not the same for different screen states.
Expected behavour: Fingreprint unlock procedure is always the same, that is: applying the finger and pressing the power button.
📌This, by the way, can be the cause of the "unlocking in pocket" effect as, based on my observations, oftentimes, when I am sliding the phone into my pocket the screen activates and a finger can accidentially touch the fingerprint sensor.
There is a setting in the Security & lock screen > Fingerprint, which is as follows:
Screen off unlock:
Option 1: Press or touch
Option 2: Press only
I think this setting should apply to all screen states for consistency.
Thank you for your feedback. But the device is working just as it was intended.
If your screen's display is switched on (due to lifting the phone or due to the incoming notification), then you can unlock the phone just by touching the fingerprint sensor.