Unlike the Wii U GamePad, the 3DS is not practical for a controller for Wii U 'cause it's NOT a controller. It's a dedicated handhed gaming device and it should stay that way. The GamePad IS a controller that is no different from a 360 or PS3 controller, except it has a screen on the middle. Dreamcast controller, anyone? The 3DS, Vita, Smartglass Tablets, Including iPad and Adnroid, etc, should NOT be implemented as gaming controllers 'cause it's not integrated like the Wii U GamePad. Those mobile/handheld devices are just additive implemetations. The GamePad is and always be a intergrated gaming controller 'cause it IS a controller that includes everything what's in a full traditional controller like in a 360 and PS3 controller.