If a Redeemable image shows as cropped or stretched within the app, it is possible that the incorrect aspect ratio/resolution was used in the original image. If the incorrect sizing is used, the expected behavior of the app is to stretch or crop the image.
The preferred ratio for images used for a vertical redeemable image in Punchh is a 9:16 aspect ratio. The preferred resolution for this ratio is :
720px X 960px