Emptying your trash folder on a regular basis is a good email practice because it frees storage space on your account. To empty the Trash folder:
1.Tap the Nav Icon at the top left corner of the Nav Bar to display the Navigation Drawer.
2.Tap Empty next to the Trash folder.
3.Tap OK when you see the confirmation screen.
Note: You will receive notification that the Trash folder was successfully emptied.