TuneIn Radio: A fantastic radio app an unfathomable amount of stations, both local and global, that you can jump in on whenever you want. If browsing is too daunting, you can search for songs or artists and zero in on the stations currently playing them. The app supports backgrounding in iOS 4.2 and can be controlled with iOS's built-in playback controls. Best of all, it basically works like a DVR for radio-you can pause a live stream, rewind back to catch a song you liked, record a station, etc. $2
The game is basically perfectly suited to make the transition from tabletop to touchscreen. It consists of a bunch of square tiles, each with features of a map on it. Elements include parts of roads, parts of cities and cloisters. You take turns placing the tiles down to create a finished map.
The actual competition comes in while you're making the map, as you're trying to complete various elements without letting your competitors complete theirs. So you're trying to build a big city or long road, while your opponents are trying to keep you from completing it or to hop on board to steal its points for themselves.
The iPhone version is a perfect translation of the game, one that improves upon the original with a solitary mode, very good computer opponents and the ability to see just what tiles are left and what moves are and aren't possible.
You can play either locally or online against friends or strangers, and a game can be banged out in about 10 minutes if you're playing against the computer or speedy opponents. It is incredibly fun.
Now it's embiggened for the iPad, and it's $10.
CNBC Real Time: A well-stocked stocks app with real time quotes, interactive charts, currencies, commodities, a customizable and flickable ticker, news, video, and, perhaps most impressively, a slick design that makes it all somewhat manageable. Free.