I agree with John Gruber on this one, so far Tweetie is the best iPhone app for Twitter out there (I’m sure more are on the way). It’s meets most of my mobile Twitter requirements. You can download it for $2.99 from the iTunes Store.
Here’s a breakdown of it’s features:
– Handle multiple twitter accounts.
– View your timeline, replies, direct messages and favorites.
– Browse your friends and followers.
– Post new tweets, retweet
– Reply directly to tweets and send direct messages.
– Follow and unfollow people.
– Mark tweets as favorites.
– Navigate reply chains.
– Inline web browser.
– Post links with automatic link shrinking via bit.ly.
– Upload pictures to twitpic.com.
– Update your twitter location.
– View twitter trends and perform custom searches.
– Save your favorite searches.
– Implements the full twitter API.
– Uses secure connection (https).