Would be INCREDIBLY helpful if we were able to read messages sent to us, then go back and "Mark it As Unread" or "Pin" it in a fashion where it's easier to delineate between messages you've already replied to or those you still need to act upon. Apple changed their text messages a few years ago to finally allow for messages to be read, then marked as unread to help users know which messages still needed to be replied to. Any change such as what I'm suggesting would make all the difference in the world to the usability of this app!