This is a bit further than some of the descriptions that I have had here for similar effects across screens. Essentially, this is again using the camera-equipped mobile as an input screen to drive any number of larger screens. There’s a good bit of AR at play here, but also there’s this melding of spaces so that you are enabled by the windows around you to interact rather than constraining that into a smaller imput device only.
Original post; found via Ubergizmo