- Simplified to single OkHttpClient — Android OS routes correctly: 10.42.0.1 → WiFi (Pi hotspot subnet) yaris.ceaf.dev → cellular (WiFi has no internet) - Removed NetworkBinder-based per-socket binding (EPERM on Pixel, OS-routed approach works better for this use case) - Verified on real Pixel: Pi GPS + server health both return 200 simultaneously while connected to "yaris 911" hotspot