My Theta Z1 cannot connect to my iPhone (SE2) hotspot. My OS was 14.8. I updated to 15 and still cannot connect to the iPhone hotspot.
But it can connect to my old iPhone (6 plus iOS:12) and my wife’s iphone (x iOS:14.7) hotspots. Their OSs are older than 14.8.
It also can connect to Android phones hotspot but not iPhones (new OSs).