IM or Chat Messenger is feature to communicate to Internet users who are online around the world by using the typed text on devices connected to the internet. You can send messages to your contacts, change your status and display picture, and organize contacts into contact categories. During a chat, you can send files such as voice notes and contact attachments. If your device has a camera, you can send pictures that you take with the camera.
Basically all the features are similar to the one on BlackBerry Messenger and it runs on Java (J2ME) supported device. This application is also able to aggregate other IM like Yahoo, MSN, GTalk, etc. For further detail there is an RFP (Request for Proposal) to analyze.