Yes!
In UAPP, start UPnP Renderer, which will make it a UPnP renderer and library.
Then on your iOS device, install mConnect (or other UPnP control point). It should see the UAPP UPnP Renderer and let you choose it as destination. You can then play music EITHER stored locally on the mConnect device OR streamed from Tidal or Qobuz, directly on the UAPP device. You log into Tidal/Qobuz in mConnect and it pulls the stream from the streaming service and passes it to the UAPP UPnP renderer.
You can also play files stored on the UAPP device by accessing the UAPP Library in mConnect, in which case UAPP picks up that it's playing a local file and avoids receiving it over the network.
I don't know about iOS, but on Android there are many UPnP control point apps, of which BubbleUPnP is the most famous and the most well developed. It has a slightly unwieldy UI, because it has SO MUCH functionality. But it can be trimmed down to exactly what you need. It's a very powerful app.
But for streaming from Tidal, mConnect has the advantage of full MQA support, whereas BubbleUPnP only supports the HiFi layer (max 16/44). Any HiRes Master tracks are down-sampled and truncated to 16/44 by Tidal, the same as if you select HiFi Quality in the Tidal app.
Interestingly, that still works for 16/44 MQA files, although they won't have any origami to unfold. Other MQA tracks with 44KHz base sample rate (such as the 2L ones) will be truncated to 16-bit, but not re-sampled, and STILL authenticate on an MQA DAC. The article linked below describes how that is possible. Of course much information is still lost in that truncation.
https://bobtalks.co.uk/blog/science-mqa/16b-mqa-what-is-it/#
For users who don't care about MQA, I recommend BubbleUPnP over mConnect. In addition to 50X as many features, Bubble has a very responsive Dev, whereas mConnect have not responded to anything I wrote, despite the fact that I bought their app.
