With a Francophile name, mobile Twitter app Touiteur may come across as a stylistic ploy. But it's one of the good guys in the tweetosphere, with its stylish design, convenient slide-away bars for posting status updates and responding to tweets. It handles retweeting, file uploading, search, lists, and trends. Plus, it handily pops up @username options when you type.
The premium version ($2.41) is a more complete option overall, opening the door to multiple Twitter accounts, home screen widgets, URL shortening, an internal browser, and the Twitlonger service. There are other free Twitter apps that provide link shortening for free, but if you're not fussed about your 140 characters, Touiteur is easy on the eye and brain.