It changes the color "all the time" meaning whenever your trackball is lit, it is no longer white, but instead beams the color you choose.

But it can be "disabled" and revert to white. [see my pic of the menu].

And of course, you can uninstall the program and go back to virgin white that way.

And no, once activated, you do NOT have to do anything to change to or keep the selected color. The program is "always on" so to speak.