With Sid Meier's Civilization games, how you take over the world has always been up to you. You can build an army and conquer the other civilizations through brute force, or you could build an economy that is the envy of the entire world. The choices you make will ultimately determine the path your civilization will take. Do you invest money in technology and win the game by being the first to launch a space expedition to Alpha Centuri? Or are you the type to create a cultural mecca where important thinkers from all over the world flock to your cities? Or do you want to sample strategies from all four paths?

Over the years, the assorted Civilization games have won renown for giving the player supreme control over their society to dictate everything from technological advancements to military tactics. When starting the game, you choose from 16 civilizations, each with their own bonuses, abilities, and iconic historical figures. (A free lite version of Civilization Revolution limits you to three civilizations.) You can declare war on the Grecian nation led by Alexander the Great, ally with Gandhi and the Indians, and trade with Napoleon's French empire. Fans of the turn-based series of games will find the major gameplay elements of the franchise are alive and well in Civilization Revolution.

But this isn't just a simple port of an unapproachable history-based strategy game. Civilization Revolution boasts a new gesture-based interface that takes advantage of the iPhone's touchscreen technology. Building, moving, and ordering your units is a simple flick of the finger that's easy to pick up the first time you start the game. The only issue I had with the system came when I tried moving my units over long distances--I found it was better to drag my finger for shorter distances rather than chart a longer, circuitous (and often hazardous) course.

On any other platform, a typical Civilization game session can run as short as an hour to 10 times that, depending on the scenario. Civilization fans can breath a sigh of relief, for the depth of the mobile game remains intact, but now it's just as easy to find yourself immersed in a prolonged campaign as it is to play for a few minutes. Civilization Revolution automatically loads your progress on your active game if you suddenly exit the game to receive a phone call. There is also an easy-to-understand save system with frequent reminders to save throughout your play session.

Besides the 16 playable civilizations, you can also pick from several difficulty levels. The game's tutorial does a good job of walking you through the steps toward making your small village into a global empire. You'll learn how to found cities, how to build your population, recruit and move a military unit, and invest in technologies.