Have you heard of Agile Messenger? With more than 400,000 users, it is probably the most popular Instant Messenger for mobile phones on the market today.

Agile Messenger Features:
- sending and receiving instant messages across MSN, AOL, Yahoo! and ICQ networks
- Push to Talk
- Unicode and BIG5 support for international characters
- split screen messaging interface
- separate tabs for each conversation
- conversation history
- smiley support
- automatic download and updating of the contact list
- contact status information and presence management
- adding, removing, renaming contacts
- data usage counter
- auto update downloader and installer
- picture messaging with camera support
Now, even more interesting part – Agile Messenger is coming to the Symbian OS V9 platform with both S60 3rd Edition and UIQ 3 interfaces. Preview release 1 is available for Sony Ericsson UIQ 3 phones (Unsigned, you will need to configure your phone to accept unsigned apps) and preview release 2 for Nokia S60 3rd Edition phones. Here’s the link to the download page.