It's really great, (one of most interresting games that I played on mobile) but I have a few questions:
1) How do you save?
2)Sometimes the enemies are invisible. Is it intendent?
3)If you mine stones that are close to magnetic lava, the stones fill fly offscreen. Is it because the lava is magnetic or is it just a bug?
4) And the menu button does not work.
Maybe it's because it's still in development, maybe not, but this things are somewhat annoying. But still I think it's a really great game.
I played it on android.