If you bought a backlit mini keyboard you will probably notice that the instruction booklet is pretty useless. Here is some information on the keyboards that might help.
*Tip : To extend battery life turn the back light off during the day and on when it's dark. Press and hold the FN button and hit F6 or F2 depending on which keyboard model you have, It's usually marked with a light bulb or a sun symbol.
Occasionally there will be a issue where your keyboard will not respond. It can be a couple things. Keyboard has a low charge, A pairing issue that may be resolved with pressing the FN + RF key and last but not least a faulty keyboard. So far every issue that was reported was solved by either charging the keyboard or the FN + RF Key fix. Please make sure you try everything I have described above.
Closing all background apps on your android tv box with your keyboard
If your android box does not have a way to close each page you have opened here is an alternative method you can do with a keyboard. This has worked on the majority of devices I have tested so far. It can be any keyboard from the small mini ones to large USB keyboards.
Press the ALT key and keep it pressed.
While holding the ALT Key press the TAB key once and the background apps will come up.
Keep holding the ALT key and press the back arrow button
Keep pressing the back arrow to close each app running in the background.