Yeah, it’s not really optimized for mobile, most of testing was done playing on a computer, with keyboard and proper display. I think it’s not really suited for mobile, it’s frustrating on a PC as well, I can’t see myself playing it on mobile.
Minor feature request: In the start when there are three buttons to pick the mode, I 'd like to use the mouse.
Big feature request: I made a similar simulator a long time ago, and I wished to add an option to show the expected trajectory in the future as a help. Also, show the trajectory in case I press up and in case I press down, so I can get some intuition about the change of the trajectory. (I'm not sure if it's possible to do this fast enough. I never added it to my simulator.)
Yes, atmospheric drag applies in the circle.