Echofon (formerly TwitterFon) is a simple and easy to use iPhone Twitter app with many features.
The pro version (for $4.99) comes with much extra features like supporting multiple Twitter account, push notifications , sync Echofon iPhone with Echofon Firefox plugin (TwitterFox), ad free, bit.ly and Flickr integration, and others. Check all features of both versions here.
Pros & Cons
|Very simple interface||Doesn’t support accepting follow requests to private Twitter account (has to be done from the Twitter web)|
|Sync with Echofon Firefox plugin (TwitterFox) – Pro version|
|Supports push notifications – Pro version|