VolcanoROF, free Android game

This is a simple and fun Sci-Fi game. You fire electromagnetic (EM) canons to stop volcanic eruptions and remove volcanoes. Level 1: Volcanoes started erupting one by one. You fire EM canons to stop them. Level 2: Volcanoes started erupting all at once. You fire EM canons to stop them. Level 3: You are surrounded by two rings of moving volcanoes. You fire EM canons to remove them. Then, one gigantic volcano started erupting. You fire you last EM canon to stop it. You are a hero!