To integrate Firebase push notifications in an Android app, you need to follow these steps:

1. Add Firebase to your Android project: Follow the steps in the previous answer to add Firebase to your Android project.
2. Add the FCM dependency: In the project’s “build.gradle” file, add the following dependency to the dependencies section:

3. Create a service to handle incoming messages: Create a service that extends “FirebaseMessagingService” and override the “onMessageReceived” method. This method will be called when the app receives a push notification.
4. Register the service in the manifest file: Add the service to the manifest file and set the “android:name” attribute to the fully qualified name of your service class.
5. Request notification permissions: Request notification permissions by calling the “requestPermissions” method in your activity.
6. Subscribe to a topic: To receive push notifications for a specific topic, call the “subscribeToTopic” method in your app.

That’s it! You have now successfully integrated Firebase push notifications in your Android app. You can now send push notifications to your app using the Firebase console or the Firebase API.