Got an iPhone and want to twitter using a slick interface. You might want to check out Hahlo. It rocks.
Hahlo is an iPhone-styled interface for the great Twitter service, and it is built upon their simple API.
All you need to use Hahlo is a twitter account. Your login details are not stored by hahlo.com, they are saved in a cookie to allow access to things such as your direct messages, and enable you to update your status directly from hahlo.
Via: Colin Devroe