[Takashi] Tezuka told Polygon the people on the tools team typically don’t design video game courses — they only build the tools for Nintendo’s game designers to use. In this particular instance, the tools team was working on a Mario course editing tool when they decided to pitch it to Tezuka as a standalone game.
The Wii U GamePad + TV is effectively a gigantic Nintendo DS. Nintendo found success in the interactive second screen experience of the DS. Mario Maker seems like a great way to push the GamePad. Rather than pushing a passive off-screen experience, taking a note from the DS is a fantastic idea.
Aside from unboxing my Wii U, I had completely glossed over the GamePad stylus.