Lightum is a MacBook automatic light sensor daemon, it reads data from the ambient light sensor (located on the iSight camera) and automatically light up or dim the keyboard brightness and screen backlight.
It will also dim the keyboard brightness and screen backlight when the computer is not used for a configurable amount of seconds.
If you choose to run it in “manual” mode, it will not query the ambient light sensor, but instead it will use the brightness and backlight values you set manually using the function keys.
There’s also an indicator applet available to control lightum from your desktop panel.
Install Lightum in Ubuntu:
If you’re on Ubuntu 12.04 Precise and its derivatives, press Ctrl+Alt+T on your keyboard to open terminal. When it opens, run below commands one by one to install it from PPA:
sudo add-apt-repository ppa:poliva/lightum-mba sudo apt-get update sudo apt-get update lightum lightum-indicator
For Ubuntu 13.10, Ubuntu 13.04 and other editons, download and install the DEBs (not tested):
For more, see lightum on github