I have a rooted Nexus 7 which I'd like to use in conjunction with a large external USB drive as a high-capacity music player. The music player provided with Nexus media importer is pretty basic (no playlist/search functionality etc), so I was wondering whether anyone had any good ideas for turning the USB/OTG media player into a more "native" style solution. For example, is it possible to mount the USB drive so that it would be visible to something like Doubletwist?