This is Lumino City. It's the sequel to a 2012 game, Lume. It's "handmade" in the sense that rather than being built from digital 3D assets it was mostly filmed on a set made in the real world.
Even the effects are done — for the most part — for real; the windmill spinning in the town isn't animation, its footage of the windmill actually turning thanks to a tiny motor.
It will be out on PC, Mac and Linux in coming months. An iOS version will come later. It's so, so beautiful.