With the introduction of FCM (Firebase Cloud Messaging) as a new version of GCM (Google Cloud Messaging), all our Android app publishing clients need to upgrade to FCM before April 11, 2019. We recommend you upgrade at the earliest so as to avoid any last minute hassles and immediately start taking advantage of the new features introduced in FCM.
With FCM, you’ll be able to securely send notifications and data messages to Android at no cost. In addition, you’ll experience an easy to use notifications interface in the Firebase Console to easily test and target notifications.
For the projects using the GCM APIs, you’ll need to update your server key and upload the .json file to migrate to FCM. As a result of this, your existing GCM tokens will continue to work with FCM without any interruption in services. This is essential as GCM server and client APIs will be deprecated and removed on April 11, 2019.
Please check this support article for a complete walkthrough of the FCM upgrade process in your apps.
If you’ve any other questions, please contact our support team at firstname.lastname@example.org.
Look forward to serving you better!