If you post an image and want to delete it for any reason, here's how to do it:
  • Tap on the post, which will open the single post view.
  • Tap on the 3 dots at the top right of the screen
  • Tap delete from the pop up menu
  • Confirm and you're done.

Attached is a screen shot of the single post view after tapping those 3 dots at the top right, showing you the option to delete.