I have two IMAP email accounts on my iPhone 5S running iOS7.
With the iCloud account, I can perform an easy swipe left gesture and select "trash" for individual emails (see first image, black boxes added for redaction):
However, using the same gesture in my Gmail inbox, I'm presented with "Archive" rather than "Trash" (see screen capture below). From here I have to hit "More > Move Message... > Trash" to delete it.
How do I set either my Gmail preferences or iPhone Mail preferences to mimic the behavior of the iCloud account's "Trash" option when I swipe?