How would I program the ability to change brightness in-app? I know that its possible as I have seen at least three apps that can do it. This would be very useful for my app
The UIScreen class has a new property called brightness.
In addition, there's another property called wantsSoftwareDimming that (when set to YES) allows you to go below the lowest brightness supported by the hardware, because a special "dimming view" is overlaid over the screen to darken things even further.
The brightness property takes a float from 0 to 1. So:
wantsSoftwareDimming set to NO (the default), a brightness of 0 means "the darkest the hardware supports" and a brightness of 1 means "the brightest the hardware supports".wantsSoftwareDimming set to YES, a brightness of 0 means "the darkest the hardware supports PLUS darkening by overlaying a dimming view", and a brightness of 1 still means "the brightest the hardware supports".