1. Open the inbox and then tap on “Edit”
2. Tap on any message on screen so the checkbox appears next to it
3. Now press and hold the “Move” button with one finger, and while holding the “Move” button, uncheck the message you previously checked
4. Now release the “Move” button
5. You’ll now be at the Inbox selection screen, at the top of the screen will show how many emails are selected, choose the “Trash” icon to move them all to trash and permanently delete them