Ive been meaning to start practicing for the GMAT for some time since I will be taking it next summer. I downloaded a bunch of GMAT apps that I found in the App Store, some of which included video tutorials and what not. I was not really practicing with the other apps though, as they dont really track your progress and help you find out where you went wrong and how to improve. The Economists GMAT app is the whole opposite. It is designed to be extremely intuitive and user-friendly and helps you track your progress along the way. It teaches you how to use the most fundamental techniques for the GMAT from the very beginning, such as ballparking, and how to apply it to the different types of questions. Overall, best GMAT app I could possibly imagine - I even doubt if taking the GMAT class is worth it anymore as Ive seen tremendous progress just from using the app!