Back in March 2013, developer Goodgame Studios launched an action-packed strategy title named Empire: Four Kingdoms.

Fire up Empire: Four Kingdoms, and you're thrust into a dangerous fantasy world that plays home to millions of real-world players from around the globe.

Your aim in this massively multiplayer strategy title, then, is to craft your very own empire from the ground up. How? By establishing a flourishing economy and, in turn, improving various aspects of your kingdom.

Naturally, as you continue to thrive, you'll attract unwanted attention from other players, who'll send out large armies to attempt to halt your advances.

This means you'll have to construct defensive fortresses; train soldiers; and even team up with your buddies and their legions of warriors in order to capture enemy outposts and ensure your survival.

Empire: Four Kingdoms was inspired by Goodgame Empire, a successful browser game developed by, you guessed it, Goodgame Studios.

According to Goodgame Studios, Empire: Four Kingdoms begins with a short tutorial rather than a long-winded seminar through which you're forced to trudge.

This simple tutorial makes Empire: Four Kingdoms a rather unique strategy game, as you can be building a castle or forming a strong alliance with a player within minutes of opening the app for the first time.

Goodgame Studios have already updated Empire: Four Kingdoms several times since it was released last year, but Goodgame Studios intend to extend the life of its app even further.

Goodgame will add an extensive achievement system to the game sometime in the coming months, for example, which will allow you to collect points and even win rewards as you go about your business.

In other words, you'll have another reason to continue playing.

Empire: Four Kingdoms is a free-to-play title, so you can download it right now without putting your hand in your pocket. You can spend some cash on optional in-app purchases later, should you wish to do so.

Goodgame Studios really want everybody to play their games, which is why you can download Empire: Four Kingdoms for free.

Goodgame Studios also believe that free-to-play is the future of the App Store, and will continue to use this payment model in future.

Head on over to the App Store and start playing Empire: Four Kingdoms now [download].