Lux Auto Brightness v0.60

Lux isn't your ordinary brightness app. It intelligently adjusts the brightness
of your display based on the environment you're in. If, for example, you step
into a dimly lit room, Lux will automatically lower the brightness of your
display to make it not only comfortable to read, but to also preserve battery
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More: http://mobilehere.net/2012/06/lux-auto-brightness-v0-60.html