Now that you've started writing some code, you can start talking to users!
Here's some quick feedback I've got:
-It's a little hard to tell where on the screen I can touch to move the miner vs. where I can shoot. Perhaps but a line on the bottom demarcating where touches will move instead of shoot?
-Perhaps the game would be more fun if the movement was faster? If you sped it up, it would make it easier to grab 2 pieces of cheese on the same row. It's up to you to decide how to balance control responsiveness vs. difficulty, but it's worth testing it out.