Twixr is a Flash Lite twitter client for Nokia phones. With Twixr you can easily use your mobile phone to tell your friends where you are or what you are doing. This application is compatible with almost every latest Nokia model and will soon be available for other mobiles.

Share pictures from your mobile phone. Automatically publish them on social networks and photosharing sites. Tell your friends where you are and what you are doing. Automatically add your location to your pictures and status updates.

Twittai is a Java mobile application which lets you tweet on your cell phone.

twibble for the desktop is a feature rich multi-account microblogging client for twitter, identi.ca, corporate and private laconi.ca instances.

Tweeter is a simple java-based Twitter client with proxy support.

Love Twitter and love tweeting from your mobile device? But don't want to get dinged for updates and double dinged for friend updates continually arriving via SMS? Tiny Twitter is just what you are looking for and it will work on ANY Java enabled phone (that's a bunch & includes the Blackberry) and ANY Windows Mobile Pocket PC or Smartphone (they're pretty cool).

jTwitter is a Java application that you install on your phone. It allows you to enter twitter updates using your phone without having to send SMS's. It also allows you to view your timeline and your friends timeline.

jibjib is another open source J2ME Twitter client designed for all twitter-ers on the road. One hand controls the wheel and another hand tweets along the road. Below is selected features list.

Fring is a mobile internet community and communication service that allows friends to connect, share experiences and enhance their online communities together. Fring features Twitter integration.