been using and experimenting Hiby R6Pro pairing with Poly. since R6Pro is android without phone properties, ive tried the apps first on my android phone before trying them with R6Pro-Poly combo. what worked for my phone and Poly, experimented with it on R6Pro and Poly. sofar, the most versatile android app I have tried using is mConnect.
using the R6Pro's hotspot, I can:
1. play music with R6Pro as the source [server] and Poly as renderer (bit perfect).
2. play music to Poly while browsing Poly's SD card contents in the R6Pro.
3. play music from Poly's SD card and R6Pro as the renderer.
using a hotspot with internet access, still using mConnect, I can do the above, plus play Tidal to Poly bit perfectly, although MQA playback is not supported. with mConnect, the albums are well categorized, displaying hifi albums and masters albums separately.
still with the R6Pro-Poly combination, two more android apps that im using is BubbleUPnP and XiiaLive Pro. BubbleUPNP can perform all of the above, except that with Tidal, the albums are not categorized and Tidal music is played at 16-44.1 flac. using the XiiaLive Pro in conjunction with BubbleUPnP, I can stream internet radio stations and podcasts from the R6Pro to Poly [Poly is selected as the renderer in BubbleUPnP].