The original Plants vs. Zombies game was an extremely fun take on the tower defense genre and started on the PC before moving to other platforms. Plants vs. Zombies 2: It's About Time was made available today for iOS devices and is free to play. The game will follow the "freemium" pay model of many other games, allowing users to make in app purchases of things like new plants. Users will still have to defend their base from the zombie horde, but instead of a home they will visit locales like Ancient Egypt and the Wild West.
Source: Apple Insider