By selecting "Reply" from the list of message options, the post you are replying to will be quoted above your reply in the chat.
As long as the author of the post you are replying to has notifications turned on, they will receive a notification of your reply post.

1. When you find a post you would like to reply to, just tap and hold down on that message until the options appear
2. When the message options appear, tap on "Reply" (For a quick way to reply, users can also just swipe right on the post you wish to reply to)

 







3. Once you tap "Reply" the chat will re-open and the post you are replying to will now be displayed above the area for you to type your reply. At this stage, users can also add a GIPHY image

 




4. Now just type your reply and tap the blue continue arrow to send
5. If at any time you want to cancel your reply before sending it, all you need to do is tap on the small (x) in the top right of the reply area (see pic above)