Sensor works very well, both on 4S and 5 but people do not know how to set it correct.
1. You need to set slider on minimum brightness
2. Turn auto-brightness one ON/OFF and set it on ON, than it will adjust automaticly
The auto-dim feature got significantly improved in iOS 6. The best improvement is brightness adjustment in the lock screen. Before, in a dark room, I would be blasted with the iPad or iPhone’s default brightness before sliding to unlock and having it dim down to match the room’s brightness. Now, from the moment the screen turns on, the brightness is appropriate.
In all previous versions of iOS, the light sensor would sense the room’s brightness and then suddenly make the brightness adjustment. In iOS 6, the auto-brightness adjustment is gradual and much more subtle, like the Mac. "
Thanks to mqudahfor the answer.
Unfortunately, the brightness will adjust up in a bright room but will not go back to dim in a dark room. It gets stuck and doesn't adjust the brightness down anymore, until screen lock.
Could you explain in detail step by step?