Azendoo is designed to support both asynchronous AND synchronous use of messages and comments (IM-like).
Both Messages and Tasks allow comments to be instantly displayed with no user-action required.
This allows for example to live-view others comments while yourself typing a comment.
Only new conversations are notified thanks to a banner to release their display.
This works on any Messages page (All messages, Workspace>Messages or Subject>Messages), and any detailed Task panel for 2 or more people viewing the same conversation and/or task.
If people are not available or on another page/tab, the message is of course available for later read. It is notified in the top-right notification area and people can choose to receive a notification email or not.