Firebase

• https://firebase.google.com/

• https://en.wikipedia.org/wiki/Firebase

Firebase is a platform developed by Google for creating mobile and web applications.

Cloud messaging

• https://firebase.google.com/products/cloud-messaging

• https://firebase.google.com/docs/cloud-messaging

• https://console.firebase.google.com/project/_/notification

• https://console.firebase.google.com/project/bitarus-sandbox-fcm/notification