tweetero is a free Twitter app for your iPhone, which supports posting images, video and location posting.
For free Twitter apps, tweetero has the basics covered. You can tweet, re-tweet and forward messages. There is your main twitter feed, plus separate feeds for mentions and private messages. You can also check your followers and tweeters you're following.
Settings are very basic - tweetero doesn't support multiple accounts, so if you want to check another one, you need to sign out and in again. There is also no search included. This means it's useless for checking Twitter trends, and anything outside of the people you already follow.
tweetero's design is simple and functional, but with nothing that makes it stand out from the crowd. While it works well at what it does, the features that are missing make it all too average, and the official Twitter app blows it away.
There's nothing special about tweetero, and in a crowded market, it's hard to recommend above the competition.