waddit is similar to the phrase “fuck it!”, however not as verbally abusive (vulgar), and more like “sod that”.
you would use “waddit” to excuse yourself from a nincompoop (a wad).
person 1: “so you want to tap the button with three dots”
person 2: “what button?”
person 1: “the one with three dots”
person 2: “whats a dot?”
person 1: “waddit.”
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?"