I already sang the praises of Fieldrunners 2 when it hit the App Store last week, but it's worth one more spotlight. Tower defense is one of the most well-traveled genres on the App Store, but Fieldrunners 2 really does bring a lot of innovation to it, and it does so in such a well-polished and perfectly crafted package that this game really is something special.
As mentioned before, there are many new stages and towers. My favorite advancements are little things like the painted paths and the subtle tweaks in AI that Subatomic Studios has put together. The new modes put lots of new angles on this old genre, and even things like the Puzzle mode aren't always super successful, but at least they show that Subatomic is leaving no stone unturned when it comes to thinking up interesting and fun ways to play this kind of game.
The current app is iPhone only, but an iPad version is due out as soon as it's ready. Meanwhile, if you like tower defense at all, or simply want to see the best the genre has to offer, Fieldrunners 2 is available for US$2.99 right now.