Probably all you NDX owners know this but just in case anybody doesn’t …
As my NDX does not have airplay, I thought I could not stream from the Apple app, But I connected my iPad using a lightening/USB type A cable and once you get a track going using the buttons on the NDX you can then control everything from the music app on the iPad. It sounds really good and you get a better interface than the Focal Naim app. This might be sacreligious but you can use EQ and I like the Late Night setting with older recordings.
The NDX2 won’t work using an iOS device via USB. The 1st gen streamers did it (using Apple’s ‘Made for iPod’ certification) as an alternative to Airplay.