What is UPnP

HD files, those that you cannot play with AirPlay or Bluetooth without losing quality, are found in local music, or on premium streaming platforms, such as Tidal or Qobuz. 
Fortunately, there is UPnP, and the good news is: there are universal and not too expensive apps that can be used to play local music or Tidal or Qobuz directly on Phantom I, Phantom II and Expert Pro