Send notifications to your firebase apps through this one. Set your title, body, sound, badge, and an optional data payload of custom key-value pairs. Store your apps tokens and test-devices to use them again easily. Check your sent notifications and use them again. Firebase Cloud Messaging (FCM) is a cross-platform messaging solution that lets you reliably send messages at no cost. You can send notification messages to drive user re-engagement and retention. For use cases such as instant messaging, a message can transfer a payload of up to 4000 bytes to a client app. FCM automatically displays the message to end-user devices on behalf of the client app. Notification messages have a predefined set of user-visible keys and an optional data payload of custom key-value pairs.
