Lately I've been hearing all kinds of postitive things about SteamWorld which just released for the Nintendo 3DS eShop. Before I get into this I'm not saying Steam World Dig is a bad game. In fact, it looks really fun. However, there is something that I would like to point out that some people may have not been aware of.
There's a game on the android market called "Gem Miner". Steam World Dig is better compared to that than Metroid and Terraria.