Plants vs. Zombies HD

Plants vs Zombies HD has a LOT more content that the iPhone version. It has only one new minigame which doesn't exist in the PC/Mac versions, but the iPhone version has NO minigames, just the ability to replay levels. Also, the HD version includes six survival modes including unlimited, none of which are on the iPhone version, which improves replayability a lot, so there is much more than just improved graphics.