If you enjoy shopping at Gamestop...

Then this app is for you... however, the company hardly updates their own app, so expect it to not work sometimes and have poor indication of inventory. You are better off using the website via PC. From a functional standpoint, the app works, but its hardly ever updated and is usually poorly optimized. IMO, you are better off not using it.
From my experience, I ordered a dark souls 3 pre-order back when it came out 04/2016. Ive picked it up in stores on release day and its still being delivered according to the app. Its now 11/2016... Ive also traded in 20+ titles since that dark souls 3 release and my trade in credit has stayed the same for even longer I think... just some perspective.

ComputerGUY24 about GameStop, v4.0.4