Sorry to hear that it is too slow for you. I think the game's speed is more influenced by the hardware than on the browser you play it in. In fact it's a large world to render (you'll notice if you make progress in the game). I hope you can get to the stage that you can burn giant pieces of land.
Make sure that only the visible part of the world is bein rendered/loaded instead of the whole world all the time. That will help performance on any device.
