We don't have a specific release date outside of "Holiday 2020" for Microsoft's dual-screen phone, but at least we know there's a working prototype out there. The company's CEO Satya Nadella is spotted with the Surface Duo while he was talking with the editor of Yahoo Finance Brian Sozzi. It isn't a great look at the device, unfortunately.
The Surface Duo is a foldable, Android-powered device, which has been skinned to work more in line with Window's design.