Twitter introduced a new interface optimized for mobile phones. It is focused for an improved experience on Android, iPhone, webOS and Nokia S60 platforms, the interface was designed with the Twitter API. Most features from the site have been included, such as reply, retweet, favorites, mentions and direct messages. Following, search and other functions are also present.
The interface will eventually replace the standard mobile site for Twitter, though it is still under development.

Twitter has been one of greatest thing thing to hit the internet in last few years. And great thing about Twitter is it has lot of APIs which can be used to access it. Mobile Twitter being another medium to access it and now improved

Acccording to techspot, This latest development comes as Twitter seeks to turn a profit, introducing paid accounts to their business model. While their financial future may be in question, many sites and businesses are embracing the service, and being more accessible on mobile devices will help fuel that.