My father recently complained about having to delete emails from his iPhone one at a time. I chuckled, because I knew exactly what he was complaining about--you have to swipe on each email, and then tap Delete to delete the email.
There is, of course, a better way, but it's not obvious.
This is really a limitation of those little screens on phones where they have to hide features, and this is one of those that isn’t easily discoverable. If you are on your IPhone or iPad and are looking at your email, in the upper right-hand corner of the screen there is a button labelled Edit. (You would think that clicking this button would edit your email, until you tried it. You would be wrong.)
Clicking this button actually puts you in a mode where you can select a number of emails at once by checking each one (tapping on it) . When you are done, you can click that same button, which is now labelled Delete and all the selected emails go away at once. That's not an obvious trick, but it's certainly easier than swiping and tapping Delete for each individual email.
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