I saw several of Chillingo's upcoming titles at the Game Developers Conference in May. The most impressive one was Air Mail, an exploration-based flying game for the iPhone and the iPad. Not only are the graphics beautiful, but the controls must be experienced to be believed. They're precise and complex, providing a real sense of flying through the air.
The production values are nice and high as well, featuring a great story, with plenty of varied missions and extra game modes. You can follow a mission mode with the story, take on a scoring mode to try and fly as expertly as possible, or just casually explore the great environments in an Explore mode.