Good game, but...
It still needs some things.
-When I was in the shop, the window blocked the view of how much money I had.
-Needs more levels of power ups and it needs to be clearer that you've actually bought the item. I tried to buy Rapidfire and it went dim, but when I got back to the level, I'm not sure it gave me what I was trying to buy. I did have enough money. I wanted to buy 2x Rapidfire, but with it dimmed, I couldn't click a second time.
-Needs power up vs enemy strength adjustment. By level 4, there were so many enemies on the screen that I couldn't kill them in time. Just concentrating in the enemies from one side STILL allowed those enemies to reach my fire.
Other than these few adjustments, this was a fun game. :)