Alberting

Filming or photographing someone without their knowledge or permission, usually in a sexual manner or relatively intimate/private location, such as a changing room or toilet. Common methods include having a phone in an exterior pocket with the camera facing the target.

Person 1, upon seeing a phone in Person 2's pocket: Dude stop Alberting!
Person 2: I'm not! Relax dude, my phone doesn't fit in any other pocket.
Person 1: My bad bro.