A spedstain is usually used to refer to someone who doesn’t know a basic thing, or something that is obvious to anyone around them. Commonly used out of rage.
Brody: GET IT.
Claire: Where is it?
Brody: IT’S RIGHT THERE YOU SPEDSTAIN.
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.