HBO has released their very own app for the iPhone, and it's surprisingly deep for an app released by a premium cable channel. There's the obvious stuff -- you can view schedules and watch clips and previews of HBO shows as well as behind-the-scenes and other content. But there's even some cool iPhone-specific stuff, like creating SMS reminders when your shows come on, some hidden object games to play, and even the option to buy some shows with hooks straight into iTunes. The app is designed pretty well, too, and for an app that's basically promoware, there's a lot of content and features included.
It's very well done -- if you don't have HBO, you probably won't need the app, but if you are a subscriber with an iPhone or iPod touch, it's well worth the free download.