Info 2 Wakeup / lock without any button

Hi, my question is there any app that will lock and unlock the screen without touching any physical button, just like another phone i saw (can't remember which one) can detect screen interactions even when the screen is locked, two taps on the screen and it shows the lock screen, some widget to turn it off again.
I know that you'll tell me google, but that research led me to a software that messed up the phone, and had to reset the device, please understand that i post here just to have an information from someone who had experienced an app that can do those things, and if there isn't just say so.

Thanks in advance.