I just checked out your app, and think it's pretty cool. You have some great features (text and images can be moved around, opacity, etc.) and the interface for creating new presentations is pretty slick.

I know that I'm being pedantic, but it is still not good enough. Having done quite a few presentations I know how important looks are. And even though your app lets me view my presentation in full screen it still doesn't fill out the entire screen real estate. This is a showstopper for me. And most likely will be for anyone using presentation software professionally.

Maybe you should consider a small app that will show HTML in fullscreen that users can download and use when presenting.