It's definitely neat, but I feel like this has been done before without success -- examples like the Motorola Atrix, Windows Continuum, and even the cancelled Ubuntu Phone come to mind. (And, going further back in time, let's not forget the Palm Foleo!) It seems like a neat idea on the surface though, so I wonder why as a concept the phone-connected-to-desktop-peripherals thing hasn't gained more traction. My suspici…
There are also similar free projects: Maru OS (https://maruos.com) and Sentio Desktop (https://play.google.com/store/apps/details?id=com.andromium....), but not so popular.