We had a wicked flatmosphere until Pieter moved in, after that it was all tense. Then we kicked his hating ass out and got in Cherene. She makes the flatmoshere fun with her slapper ways...
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.