Zoo Tycoon 2 is a "sim" game that like its predecessor gives the player the ability to construct their own zoo. It`s also a game you can mod very easily. There are 4 XPs (expansion packs.) These expansion packs are only availble on the PC/Mac. You can`t get it on the IOSes. (does not count for the Mac.) But you can get it on the Android. You can get it on the DS, too. (it`s laggier though)