Not convinced just what like of electronics you are talking about, but that belike only works all for cell phones.

I know for a fact that when you get a untested MP3 player, the thing that drains the battery the MOST is the backlight. The high your backlighting is rotated up, the quicker your battery dies. It’s important to keep the backlighting dim and only clot for less than 5 secs at a instance.