If you're a gamer, you can consider AP (action points) in Ingress as serving much the same purpose as XP (experience points). The higher your AP, the higher your level, and the higher your level, the better the gear you're allowed to use. Your AP bar is at the very top of the screen. It's quite thin and is difficult to see on smaller phones. You can see an exact number of AP by tapping on your XM bar (just below the AP bar) or on your agent name just below that.