CometChat has a feature that displays a pencil-image next to the user’s name at the top of the chat window when the user is typing.

However, note that this is an experimental feature and may NOT work at all. We provide no support for this feature.

To enable this feature, set ‘DISABLE_ISTYPING’ to 0 in the /cometchat/config.php file i.e.
define(‘DISABLE_ISTYPING’,’0′);