I was bombed be around 280 emails yesterday, and i had a really good time manuallu selecting every mail to delete them, as there seems to be bo no way to auto select/deselect multiple mails at once and delete them in default email app
The way I do it is...press the checkmark next to a unread email...hit menu then select all, then it should give you the option to mark as read or delete all...hope that helps.
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