The latest update to Gmail (version 8.5.20) adds the option to swipe left or right to perform an action. This is entirely customizable so you have the ability to swipe left and delete the email or archive, it’s up to you.
The Update is rolling for over a week perhaps it was a server-side switch which enabled it as we didn’t spot it in the past few days.
Head over to Gmail’s general settings and you”– see Swipe actions checkbox replaced by a menu that opens into a separate page.
Tap on it and you get to choose a different action for each swipe direction. The available options are: Archive, Delete, Mark as read/unread, Move to, Snooze, and None.
Update your app by clicking on the button below.