16. Sending to Multiple Devices

If you'd like to learn more about device groups, the documentation is here.

Sample Code

The code for subscribing and unsubscribing to "country" topics is shown below.

// Subscribing to topics
FirebaseMessaging.getInstance().subscribeToTopic(“japan”);
FirebaseMessaging.getInstance().subscribeToTopic(”usa”);

// Unsubscribing from a topic
FirebaseMessaging.getInstance().unsubscribeFromTopic(“usa”);