iOS Tip 157 - Delete All Mail

1 Open the Mail app in iOS 10
2 Go to the inbox or mailbox folder you want to delete all emails from
3 Tap on the “Edit” button in the upper right corner
4 Now manually tap on every single email you want to delete, as signified by having a blue check mark next to the email message
5 Now choose “Trash” in the corner
6 Confirm that you want to delete all selected emails by choosing “Trash Selected Messages”

Repeat with other folders and emails as necessary - a bit kludgey from prior method but it works.

iOS Tip 131 - Unread Mail

Enable an “Unread” Email Message Inbox in Mail for iOS
1. Open the Mail app in iOS if you haven’t done so already and go to the primary mailbox screen
2. Tap on the “Mailboxes” button in the upper left corner
3 . At the mailboxes screen, tap on “Edit” in the upper right corner

Locate the “Unread” mailbox and tap on it so that the blue checkbox alongside is checked, then tap on “Done”

Still in the Mailboxes screen, now tap on “Unread” to open the Unread email only inbox view

This will open a special email inbox that only shows the unread messages in Mail app on the iPhone, iPad, or iPod touch, making it a very efficient way to manage an unruly inbox and triage unread messages faster.

You can return to the normal “everything” inbox by returning back to the “Mailboxes” view and choosing “All Inboxes” again, or selecting an individual email account, or another mailbox, as desired.

iPad Tip 46 (and iPhone) Customize Mail Swipe

Mail has enhanced swipe gestures for quickly dealing with messages by swiping left or right on them. You can customize these options via Settings > Mail, Contacts, Calendars > Swipe Options. You can choose from None, Mark as Read, Flag, and Archive. For Swipe Left, your choice appears in the list of shortcuts that swiping partway reveals, but swiping all the way deletes a message.

iPad Tip 41 - Preview More of Your Mail

The iPad's Mail app defaults to previewing two lines of each email before you tap on it. Sometimes however it would be handier to be able to see more of an email before loading the whole thing in, especially if you are on a slow connection. To do this open the Settings app, then tap on Mail, Contacts, Calendars and change the Preview options to add more lines.

iPad Tip 7 - Preview Mail

By default, iPad's email app is configured to show only 2 lines, probably a hold-over from
iPhone, but impractically small for iPad.
Go to Settings | Mail, Contacts and Calendars and select "5 lines" under Preview. Also, while
you're at it, you might want to update your Push email from "Manual" if you like to have your
messages waiting when you open the Mail app. Note - push features tend to drain battery power
a bit more quickly.