So I use a ton of email aliases for reasons. But I always forget how to get into the iOS settings for Mail to set them up. Every time I search for it on the web, I come up with old information or others asking the same questions.
So here are the steps I use to get into the right place and add your aliases for your IMAP email setup. I imagine it works for POP too, possible iCloud email. I just have never tested it to say for sure.
01. Unlock your phone and tap SETTINGS
02. Tap MAIL
Then simply back out as it saves your changes. Once you create a new email message in Mail, you can select the alias it will be from. Be sure to have set the email alias up on your host prior. These steps only work if the alias was already setup on the host side.
Hopefully this helps you 🙂