Over the weekend an N64 emulator app quietly made its way onto the Xbox One's app store. The app wasn't a secret for too long, it was quickly discovered, purchased, and downloaded by anyone who could either pull it up on the Xbox Store or had the extra cash to buy it (around £7.69).
The emulator, named Win64e10, arrived on the Xbox One thanks to the Universal Windows App. The app appeared once before on Windows 10 around 6 months ago, but it was unknown whether or not Microsoft would allow the emulator to release on the Xbox One.
The answer is no.
Once Microsoft recognized that the app was available and had been downloaded, it was removed from the Xbox Store. Fortunately, some players used the app while it was available to play Mario Kart 64, Super Mario Galaxy 64, 007 and more.
There's no telling how many times this app will be resurrected on the Xbox One, but maybe one day it won't get removed.