The program contains a list of all the applications that are lowering or raising their prices, as well as those that are available for free during a limited period of time. That way, you only need to take a quick glance to see if there's anything that catches your eye.
However, maybe the best feature of AppZapp is that it allows you to select applications that interest you so that you can later receive alerts and push notifications in case their prices change. Thanks to that option, you'll never miss out on an exciting offer.
AppZapp also includes a small social component that allows you to see which applications were downloaded or 'liked' by other users, making it easier to see which ones will interest you, even if you'd never heard of them before.
AppZapp is a useful tool for any iOS user, since it'll allow you to save a few bucks when buying some of the best apps available on the enormous App Store.