Jack Fish-ing is when you or another person eats food very loudly in an online call. This can apply to the crinkling of chip bags or the slurp of soup amongst other things.
Tony was eating ships so loud on Skype, I couldn't concentrate on my game. He was totally pulling a Jack Fish/Jack Fish-ing.
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.