Make your inbox more efficient
Head to Settings
In Settings > Mail, under Threading, check “Organize by Thread” is on. If not, messages from conversations are listed individually (as above). Turn on Complete Threads too and Mail will group even those messages you’ve moved/archived.
You can identify threads by a double arrow at their top right. Tap it for a list of received messages, then tap one to view it alone. Or, tap elsewhere on the row to see all messages — from participants and you — in a scrolling view (see next step).
The two other threading settings change the display in ways that can reduce the amount of scrolling in long threads. As above, read messages are reduced in height until you tap them, and newer messages are listed first for quick and easy access.