Tap Defense

Ever since Monica suggested this to me (via twitter), I've been pretty obsessed with this game - to the point where I want to delete this off my iPhone cause must sadly admit that I do get a bit too emotionally invested in this game!

Best part about it: it's free and fun.

I'm not sure what the exact premise is, but you're basically creating towers to slay demons, locusts, monsters and occasionally the devil himself to gain acceptance into heaven. It's essentially a really dumbed down version of Command & Conquor or War Craft.