Still missing in iOS 11
In response to your newsletter question about what we would like to see in future Apple OSes: I would like to see the email address included in the email’s “Inbox” title when you have more than one email address. It would make life easier when changing from one to the other. In fact it would be beneficial to have the email address included for Sent, Outbox, and Trash too. Christ ian Petersen If we follow your meaning, that is possible. Go to Settings > Accounts & Passwords, tap an account whose name you want to change. If it’s a non-iCloud account (or a secondary iCloud account), then tap Account on the next page, you’ll be able to enter a name that makes sense next to Description. That is then used as the inbox name in the top level of Mail.
At that level, tap Edit, then Add Mailbox to specify the mailboxes you want to see there. When you tap Done on that page, the account descriptions you entered earlier will be shown below the mailboxes you just added.