My Samsung Galaxy S3 automatically locks the screen after a given number of minutes. After this I have to insert a secret code to unlock. I can disable this feature, checking "Never lock screen". In this way screen will never lock (and this is ok) but as side effect it will never turn to black (this isn't ok, this will drain my battery).
I want that screen just to turn to black without locking, in this way as soon screen is touched phone is immediately active.
If I click the side power button phone will go in locked mode as usual (secret code is needed to unlock).
I've found some application that partially do this. In some case I have to click on the main button to reactivate phone, while I want that entire screen as sensible zone.
What can I do?