Skylanders: Swap Force for the Nintendo 3DS is the 3rd installment of the Skylanders series to be released for the 3DS. The 3DS versions of Skylanders are considered companion stories to their big brothers on the consoles and PC. Swap Force for 3DS has its own story and play style. Here are some of the main differences:
A different story about a villain known as Moneybone, who launches a surprise attack during the unveiling of a solid gold statue of Flynn, and in the process snatches up Cali, another main character from previous titles.
Much stronger emphasis on platforming.
Double jumping is possible with all Skylanders (there is no double jumping in the console version).
You can import all your Skylanders into the game via the portal at once and switch between them with the touch screen. This maximizes portability so you don't have to drag all that plastic out with you.