[bowlofred]

BubbleUPnP on Android can do that.  It's a paid App, but can do a lot of things.  

I don't use it in the manner you mention, but I just tried pushing music from my phone to Kodi and it seemed to work fine.  Kodi appears as a "Renderer".  Select that and hit play.

Yatse can do some UPnP things, but I don't see any way for it to use the phone as a media source, only as a renderer.