Using Smartphone/Tablet as FPV monitor

Hi,
it could be that simple: Many android tablets/phones support USB-OTG and UVC drivers. This means video input via USB.
I already can connect a video-in usb dongle to a fashark receiver and see live video on a tablet, but its a wiring mess, you need extra batteries, etc.
A simple dongle, which contains a fatshark receiver and outputc the video as UVC over usb would make my phone/tablet instantly a FPV monitor for others to whatch while I'm flying.