Set up Firebase Authentication (Google Sign-In), AdMob, and RevenueCat IAP for Flutter Android apps. Use when enabling Firebase Auth providers, configuring Google Sign-In with OAuth clients, adding AdMob ad units, or integrating RevenueCat subscriptions. Covers the exact GCP console steps, SHA-1 reg
Set up Firebase Authentication (Google Sign-In), AdMob, and RevenueCat IAP for Flutter Android apps. Use when enabling Firebase Auth providers, configuring Google Sign-In with OAuth clients, adding AdMob ad units, or integrating RevenueCat subscriptions. Covers the exact GCP console steps, SHA-1 registration, Gradle plugin setup, and real-device testing gotchas. Triggers on keywords like "Firebase