1. asking about audibility, “did you hear what I said?”
2. more commonly, it’s demanding that the listener pay attention and understand the speaker's words.
3. When used as an expression
One of anger and/or emphasis, it functions as a forceful way of saying, "Pay attention to what I'm saying!" or "Do you understand what I'm saying?" Feel me?.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"