I have the Apple bluetooth wireless keyboard that I have been using with my iPad 2, and now my iPad Air for almost 2 years. In that time, I've only chnged the batteries once (and I use this setup almost daily). For my setup, the green light on the keyboard only comes on when I first turn the keyboard on, then it goes off once it is conected to the iPad. The keyboard still works (and is working now) even though the light is not on. When in doubt if the keyboard is turned on or not, I will hit the caps lock key. If the keyboard is on, the green light on the caps lock key will turn on.