The Tribez, a popular free casual sim game for iOS, has just migrated to Google Play. A lot of the same ol' FarmVille shtick is here, where you need to check in on your buildings collect coins, grow your settlement, and supplement your progress with in-app purchases if you're feeling it. There's not much in the way of multiplayer here, but there are a bunch of missions to embark upon, resources to exploit, buildings to construct, and a little pet dinosaur to train. Over time, you can expeand your territory over 6 islands in the prehistoric area.
I've put a fair bit of time into The Tribez, and the graphics are surprisingly good for this kind of game. The in-app purchases can be a little on the pushy side, but if you're looking for a game that's a notch or two more casual than SimCity, The Tribez may be worth checking out - especially since it's free.