The iPhone seems like a pretty nice home for the ever-popular tower defense genre, but it seems like there are only a few developers making a real effort to bring that PC experience into the palm of your hands. Then Subatomic Studios came along and released Fieldrunners, quenching the thirst of TD fanatics everywhere.

If you’re new to the tower defense genre, the idea is pretty simple; every minute or so, a wave of enemies will appear on one side of the screen, trying to infiltrate your base on the opposite side. It’s your job to line up strategically placed towers around their path in order to destroy them before reaching your base. You start the game with a small sum of money – just enough to buy a few towers – and with each enemy you defeat, you stack more cash, allowing you to build an arsenal of defensive weapons.

Fieldrunners is a free-roaming tower defense game, meaning the enemies aren’t on any set path, and simply have an open area to roam around in. That means it’s up to create a convoluted gauntlet of death they have to run before getting to the finish. Since each tower can be upgraded to become more devastating, you’ll have to decide whether or not it’s fiscally viable to upgrade or to purchase a new tower. The four different defense weapons include a rapid fire machine gun, a goo-shooter, a missile launcher and the ever-expensive lightning tower. Each tower has their benefits and cost-effectiveness, so you’ll have to think ahead in considering what to purchase.