Okay, thank you. I've yet to test the game for mobile devices, so at the moment I recommend using a laptop/desktop if at all possible. As far as I know, on smaller screens there should be a small arrow in the top left corner that opens & closes the sidebar, but if that's missing then I'm not sure what's going on at the moment.
I'll try to add mobile specific support sometime in the next few updates, but can't promise an exact ETA on when that will happen.