About Chat
With Chat (network service), you can exchange instant messages with your friends. You can access several chat services or communities simultaneously and switch between them. If you want to, for example, browse the web, you can leave the Chat application to run in the background, and still be notified of new instant messages.
The Chat application is preinstalled on your device. To start chatting, select 
> Applications > Chat .
Using network services and downloading content to your device may result in data traffic costs.