I built it in Unity using the Mapbox SDK and ARCore.
Have you really never seen a sci-fi movie with a holographic map and said "that would be cool as hell"? Maybe a better answer is that static or even web maps don't always give a sense of scale and "tactility". This is one possible answer to that.
It is not yet available on any app stores, but you are more than welcome to clone the repo and develop it yourself.