If the reader has physical buttons as wel as / instead of touch screen etc.., it might be possible to rig a remote command to some kind of physical device? To press on the button? Or is that too clunky a proposition.... Wouldn't need to be enormous.
I can see that some disabilities would find something like a remote function a real boon.
[ Actually I just rushed off and tried the theory on a 650, with one of those things for picking up litter - it does actually work, much to my surprise ! Over to the engineers ? ]