Sending a Chat Message
Step 1 - Type into the 'Message' box, then tap on the 'Send' arrow
Unsending a Chat Message
Step 1 - Press and hold on a message that you have sent and tap 'Unsend Message' on the menu that appears.
Step 2 - Type in a 'Reason', then confirm by tapping on 'Unsend Message'.
The message will be replaced in the chat window with 'Message Unsent'.
Re-sending a Chat Message
Step 1 - Press and hold on a message that you have unsent and tap 'Resend Message' on the menu that appears.
Step 2 - Confirm by tapping on 'Resend Message'.
All participants will be able to see the message again in its original location.