I'll never understand why people invest so much time into the mechanics and artwork for a game like this, but settle on "music" that's just a 30-second loop that plays over and over until it drives you nuts.
Gems are used to buy certain upgrades and buildings that you'll unlock as you keep playing. Coordination levels can't be bought until you have enough housing.
I get that developers need to make a buck, but considering you can play hundreds of thousands of these for free on sites like griddlers.net I just don't see the appeal of paying this much for logic puzzles.
pineapple12: It definitely matters where you place your troops, since they can only move over the entire map in the last battle round. Get a territory next to someone's castle in the conquest rounds and you could possibly knock them out right away.
prodevel: Arabic numbers are the ones most of the western world uses (0123456789). They're called Arabic (even though they're from India) to distinguish them from Roman numbers (IVXLCDM).
I don't know if this is intended or not, but you can screw your city over by turning blocks into schools or laboratories, at which point you lose the ability to turn them back into anything else ever again.