Do you notice when receive a comment on Trello via email, you just need to reply that comment so your reply can appear on the board. This function is also available on Upwork in which I just need to reply an email to reply a message.
I wonder if you implemented this function, how would you do it? What kind of knowledge that I have to learn to do this? Do I have to mess around with mail server?
I am good at PHP and its frameworks, but willing to learn anything new.