Nintendo has revealed some of the prototypes it went through before deciding on the final Wii U GamePad controller available with the Wii U that is on sale around the world.

In an interview with Satoru Iwata, president of Nintendo, and members of the Entertainment Analysis & Development Division (EAD) at Nintendo posted on Nintendo's website, the team has said it always wanted to have a second screen this time around.

READ: Nintendo Wii U review

"As I remember it, completely separate from what kind of gaming console Wii U would be, our own team performed a number of experiments with regard to gameplay using both a small screen in your hands and the television screen," recalls Iwata, before adding, "An experiment using the Wii Zapper controller was what inspired us to put a gyro sensor in the Nintendo 3DS system, which was in the final phases of development."

While the 3DS was called back to add a gyro, the Zapper design didn't stick for the Wii U. Instead a makeshift GamePad concept was created from a screen and two Wii Remotes stuck to the side with some tape.  

"We used this prototype and two Wii consoles to run simulations for Wii U. EAD isn't a hardware department, but a 'handicraft team' knowledgeable about hardware that makes stuff like this," explains Katsuya Eguchi from the software development department of the EAD and producer of NintendoLand.

The new GamePad was actually then designed in connection with the game, which explains why many of the games specifically take advantage of the second-screen experience.