Patrick scrolls through his Instaclam (a parody of Instagram) feed on a tablet. When he sees his friends on it, he believes that they are really in it and when he sees a picture of a Triple Gooberberry Sunrise, he thinks it is real, so he eats it. In the end of the short, he takes a photo of himself.
Patrick calls mayonnaise an instrument despite learning it isn't one in "Band Geeks." It's possible this short takes place before that episode. Then again, Patrick is stupid and doesn't have the best memory.
Instaclam is a parody of the real-life social networking site Instagram.
The Gary scene is a clip of another Nick.com video, which is a reference to the popular internet video "Nyan Cat."