There are a ton load of Twitter clients for the iPhone in the app store. There's one literally for every type of Twitter user and each one has their own quirks, but the main thing they are out there to achieve is to help you in reading tweets and posting tweets super fast.
Tweetbot for iPhone does just that. Looking at tweets, replying to tweets and what not can be done super quick. And the design of the app is absolutely fantastic, seriously. For me it is the best Twitter app for the iPhone.
If you follow a ton load of people and accounts on Twitter you know how useful the lists feature can be. Organizing accounts into different lists can help you find the information you want right there then. With Tweetbot you can tap at the top to switch quickly between your timeline and lists, instead of having to dig through the app.
Conversations, Replies & Gestures
A sweet feature of Tweetbot is the gestures it has. These gestures can help you do certain things very quick and easy. If you want to see a conversation on a tweet, you can simply slide that tweet to the right. Double tapping a link, hashtag or accounts name takes you to the according place. Holding down on a tweet reveals options for that tweet. Then there is also a triple tap gesture which can be custom assigned to reply, favourite, retweet or translate.
Customizable Tab Bar
At the bottom of the app you get five bars. The last two bars are customizable. By simply holding them down you can have the bar assigned to search, lists, your profile, favourites or people you've muted from your timeline.
The only features which are missing from the official Twitter client, is the discover tab and the interactions tab. Other than this, the rest of the experience is just the same, if not better. It does cost £1.99 ($2.99) which some may feel is a bit much for a Twitter client. But you get a lot more cool features, and you get to browse through your tweets in style.