When Autocorrect fails you or a message arrives that renders the lengthy epistle you just typed irrelevant, you can easily delete entire messages or emails. Or you can recover typing you accidentally deleted or an email your misfiled.
To delete what you've typed, just give your iPhone a gentle shake and the Undo Typing menu will pop up. Select Undo. If you want to recover typing you just deleted, give your phone another shake and the Redo Typing menu will pop up.

This also works in Mail if you accidentally delete an email or save it in the wrong folder.
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