While you could always use Prover on a mobile device, following feedback, we have made some improvements.
You spoke and we listened.
You can now click the expand button to make the map full screen, as well as use mobile pinch and swipe gestures to navigate the map.
Additionally the general layout is easier to use on a mobile, and makes good use of the space across devices of all sizes, from the smallest smart phone to the largest tablet or PC.
As usual, we will keep on working to improve the product, so we always appreciate your feedback.