The old iPhone, iPad and iPod touch have a brightness sensor that allows you to automatically adjust the brightness of the screen according to the ambient light. But many users have been complaining that this feature has not worked very well after upgrading to iOS 6.
Fortunately, it is possible to calibrate this sensor so that it works again as in the manual. See how.
You will need a dark room, or a flashlight. Follow the steps:
Step 1: Take your device and go to a dark room (or place) with no light. Take your device with you.
Step 2: Open the Adjustments> Brightness and Background Image. Turn off the option Auto Brightness.
Step 3: In the dark room, adjust the brightness adjustment to the minimum possible.
Step 3.5: If you can’t find a dark room, turn on the flashlight and focus closely on the device’s camera, setting the brightness to maximum. If you don’t have a flashlight, it could be a lamp.
Step 4: Call back option Auto Brightness.
Okay, your device is calibrated and the automatic adjustment should work again after that.