Since iOS 14, it's possible to reply to a specific message in an iMessage conversation.
Just long-press on the desired message, then tap on "Reply" and write your reply.
That's it!
Blog (EN)
In this post, I will show you how to find out the exact time at which a specific message was sent or received.
By default, the Messages app groups conversations together and provide a unique timestamp, even when replies are tens of minutes apart from each other.
There is a simple way to reveal the exact time for each specific message on your Apple devices.
In this post, I will show you how to mute unknown senders in Messages.
This tip is useful if you don't want to receive a notification when someone not in your contacts list (most probably a spammer) sends you an iMessage.
It's important to understand that only iMessages are concerned; SMS messages cannot be muted, unless the sender has been explicitly blocked (as explained in my previous post).