In my experience, the Mail apps for iOS and OS X defaulted to different actions for swiping to delete or archive email messages. A swipe to the left on my iPhone brings up the archive button, and a swipe to the left on my Mac brings up the trash button. Time to get these two actions in sync.
Since I feel no need for an email archive, I just want a simple delete command on all Mail fronts. So, I need to change the setting on my iPhone from archive to delete. I will also show you how to change the setting on a Mac, however, while we are on the topic.
On iOS, head to Settings > Mail, Contacts, Calendars and select one of the email accounts you have set up in Mail. Next, go to Account > Advanced and in the Move Discarded Messages Into area, select either Deleted Mailbox or Archive Mailbox.
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Screenshot by Matt Elliott/CNET
On OS X, open the Mail app and go to Mail > Preferences. On the Viewing tab, you can choose either Trash or Archive for Swipe Left To.