One of the defining features of the Xbox One is that it has an HDMI input socket, allowing you to plug a wide range of media devices into the console. The intended purpose of this HDMI socket is to allow you to watch TV and play games side-by-side on the same screen -- but in practice, you can plug just about anything into the Xbox One's HDMI socket, including the PS4. And so that's what we did -- on a 65-inch 4K television no less.