C2 is really great not only for mobile apps but also for HTML5 and desktop aps. As — said it's easy to start with C2 and there are many things to learn which let you do even pretty complex games. However it is not a pure drag&drop. You have to tell the app how it should behave in various situations, so there is a visual programming involved (based on events and actions).
Anyway there is a free version so you have nothing to loose, just take a look. Good Luck!