Push Notifications with FCM

Learn how to add push notifications to your app with Firebase Cloud Messaging (FCM).

The Kustomer Chat Android SDK uses Google Firebase Cloud Messaging (FCM) to send push notifications.

This tutorial covers how to add FCM to your app, configure push notifications in Kustomer, and handle push notifications in the SDK for users.


You'll need the following to set up push notifications with FCM:

  • Access to your team's project in the Google Firebase console and any necessary permissions for related tools (for example, Google Analytics).
  • Admin permissions for your Kustomer organization to change Chat Management: SDK settings.

Step 1. Add Firebase Cloud Messaging to your app

First, use the Google Firebase console to add FCM to your app. To learn more, see Add Firebase to Your Android Project from the Google Firebase documentation.

  1. Open your project in the console for Google Firebase. If you do not have an existing project, create a new one.

  2. In your project, select Add Firebase to your Android app and follow the instructions to generate your google-services.json file. For your package name, copy and paste the package used in your application AndroidManifest.xml file.

  3. Save the google-services.json file generated by the tool at the root of your Android application (//google-services.json).

  4. Follow the Gradle instructions, and modify your Project-level and App-level build.gradle files accordingly:


buildscript {
   dependencies {
       // Add this line
       classpath 'com.google.gms:google-services:4.3.3'


// Add to the bottom of the file

apply plugin: 'com.google.gms.google-services'
  1. After you modify your build.gradle files, select Sync now in the bar that appears in the IDE.

Step 2. Configure Push Notifications in Kustomer


You can customize your push notifications content to redact sensitive information. To make these changes, go to Apps > Chat and select the SDK tab.

After you add FCM to your app, locate your FCM server key in the Firebase console. Once you have your FCM server key, open your Kustomer account and configure push notifications on your Chat Management: SDK settings page.

  1. You'll need your FCM server API key to configure Android SDK settings for push notifications in the Kustomer platform. To locate your FCM server key in your Firebase project, go to Project Overview > Project settings and select the Cloud Messaging tab.

    Your Server key will be listed under your project credentials.


Firebase Project settings.


Server key located under Cloud Messaging in Firebase Project settings.

  1. After you locate your server key, open Kustomer as an Admin user, and go to Settings > Channels > Chat and select the SDK tab.

  2. On the Chat Management: SDK settings page, copy and paste the Server key for your project into the Firebase Cloud Messaging Server API Key box under the Mobile SDK settings block.

    Select Save Changes to create a keyset for the Android SDK.


Enter your FCM server key to configure your Android push notification settings in Kustomer.

Step 3. Register Device For Push Notifications

You can implement one of the following options to distinguish Kustomer push notifications from your own app push notifications:


Call registerDevice after Kustomer is initialized

Call registerDevice either in the Kustomer.init() call back or on onActivityCreated to ensure your Application class has initialized before you call registerDevice.

  • Use registerDevice to have the Kustomer SDK fetch the device token from FirebaseInstanceId and to register the device token.
  • Use registerDeviceToken(token) to register the device with a token that you specify yourself.
suspend Kustomer.getInstance().registerDeviceToken(token){
            when (it) {
                is KusResult.Success -> it.data
                is KusResult.Error -> it.exception.localizedMessage

Step 4. Forward Kustomer Push Notifications to the SDK

If your Android app doesn't handle push notifications yet, the Kustomer SDK adds its own implementation of FirebaseMessagingService to your AndroidManifest and automatically handles the notifications. Continue to Step 5 to learn how to deregister devices for push notifications.

If your app already has an implementation of FirebaseMessagingService, you'll need to override FirebaseMessagingService on onMessageReceived and identify whether or not an incoming remoteMessage is a Kustomer push notification. You don't need to do anything with Kustomer push notifications because the SDK will handle these automatically. If needed, add any handling you require for the push notifications from your own app.

override fun onMessageReceived(remoteMessage: RemoteMessage) {

        //Push notification received
        val isKustomerPush = KusNotificationService.onMessageReceived(remoteMessage: RemoteMessage, applicationContext: Context, customBackStack: TaskStackBuilder?)
        if (isKustomerPush) {
            //Do nothing
        } else {
            //DO HOST LOGIC HERE


Allowed message types for remote messages

The Kustomer Chat Android SDK will ignore any remote messages that aren't one of the allowed chat Message Types.


Override for the push notification icon

To override the small push notification icon, you can create an icon in the Client app with the name ic_kus_chat_notification.


Pass an optional backstack when the SDK launches from a push notification

By default, launching the chat widget from a push notification will do so without any app Activity on the backstack and navigating up/back beyond the root of the SDK will close it. To pass a custom backstack that leaves the end user in your app after they've navigated up/back away from the SDK, you can pass an optional TaskStackBuilder.

Step 5. Deregister devices for push notifications


Deregister devices for new user logins

Always deregister the device from receiving push notifications for new user logins. This ensures that the new user does not receive push notifications for any previously logged in users.

To deregister devices for push notifications, implement the following:

suspend Kustomer.getInstance().deregisterDeviceForPushNotifications{
            when (it) {
                is KusResult.Success -> it.data
                is KusResult.Error -> it.exception.localizedMessage