When person who just bought an IPhone spends countless hours feverishly searching for, talking about and buying applications for their IPhone.
Similar to a person who is going "Ape-shit". Individuals who are going App-shit in many cases appear to be in an out control frenzy, often buying pointless apps they will never use more than once just to show them off to their friends and co-workers.
Friend 1: "Dude! George has really gone App-shit since he got an Iphone. All he's done for two days is sit in his room searching the web for apps, apps and more apps. It's kind of scary."
Friend 2: "Ha ha ha ha ha! Dude! I went totally App-shit too when I first got my IPhone. I wasted like 50 bucks in two days on Apps I deleted like two weeks later. Don't trip, he'll snap out of it after a week or so."