Neue Features:
• ❤️ Herzfrequenz-Sensor (Watch)
• 🩸 SpO₂-Sensor (Samsung Health)
• 📡 Proximity Event (Näherungssensor)
• 📡 BLE Bluetooth (Phone ↔ Watch)
• ⏱️ Timer System (start/stop/tick)
• 📳 Event System (Shake, Proximity)
• 📺 Cast Controls (Play/Pause/Stop)
• 📋 Bottom Sheets
• ✅ Input Validation (200 Zeichen)

Behobene Fehler:
• 47 Bugs fixed (12 kritisch)
• Unicode-Namen (ä→ae, ö→oe)
• Permission Rationale
• ExoPlayer Memory Leak
• Type-Safe Comparisons

Plattformen:
• Android 7+ (API 24+)
• Wear OS 3+ (Galaxy Watch 4+)
• Chromecast (Google Cast SDK)

QA Score: 95/100 ✅