Provide better browser support for mobile devices. This would involve larger buttons and some different formatting. The non-mobile version of the website would remain mostly unchanged.
Well, I don't access EvC on my smartphone because the keypad is too small for my old fingers, the copy and paste functions are pathetic, and I don't have access to the saved information on my laptop.
But I do occasionally use my galaxy tablet. My advice would be to ensure buttons are left oriented and have space below them so they aren't lost outside the visible window. I have a bluetooth keyboard for the tablet, so it becomes a mini laptop.