I frequently minimize images and add occlusion masks to them. I found it’s a bit annoying if I want to view these images with masks on mobile devices because when I click on those, the answer will show up directly.
Besides, swiping up or down to determine the difficulty level of a card may not be useful as expected because on mobile devices buttons are just near my fingers.
I guess it is better for users to determine whether they should trigger clicking or swiping effect in the queue in the options panel.