Spacetime Studios' Pocket Legends [iPhone, Free / iPad, Free] has been the talk of the town since the iPad client was first released along side the iPad last Saturday. We've already posted about the game between its announcement and a comparison between both the iPhone and iPad clients. Also, we have threads in our forums for both the iPad and iPhone versions of the game if you're looking for someone to play with.
So there you have it, both clients are now available, and completely free. People in our forums are loving the game, and while I haven't been able to invest too much time in to it yet, you've got nothing to lose by giving it a spin.
App Store Links: