iPhone users were stuck with third-party apps to access their accounts until Twitter decided to get in the game in mid-2010. The company bought Tweetie 2, a popular Twitter for iPhone app and revamped it into a better user experience as an official Twitter for iPhone app. Add your account and tweet, send DMs, share photos, videos, and links directly from your phone. The app also easily updates the latest tweets with a pull-down auto refresh functionality that not many apps out there have yet (but probably will soon).
Price: Free via iTunes
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