Firebase Cloud Messaging (FCM)

• Used to send/receive messages to peer devices (iOS, Android, Web)
• Messages can be addressed to single devices, groups of devices or topics
• The mobile device app instance register itself with the firebase cloud messaging server
• On your backoffice, you submit a request to firebase cloud messaging server to send the desired message to a target

Message types

• Send push notifications to devices
• Send data to devices. E.g., posts, comments

Token

• The message can be redirected to a specific device using a token
• The token is assigned to a device at the application startup
• Ideally the token must be cached in the device's internal storage

Permissions

• The device must have permissions to receive notifications (must be allowed in the device)

App State

• Foreground
• App is open
• Normally the notification is not received (because it's already open)
• Background
• App is minimized
• Notification is delivered
• Terminated
• App is closed

FCM Console

• It's possible to send messages directly from Google Firebase Console (without an internal backoffice)

• Access your firebase project in the firebase console and find it under Cloud Messaging tab

• Notification

• Title

• Text
• Image (optional)

• Name (optional)

• Target

• User segment

• Topic

• Groups

• Scheduling

• Now

• Tomorrow

• ...

• Conversion events (optional)

• Send notification upon an event (goal metric)

• E.g., first_open, in_app_purchase, etc

• Add Analytics label for metrics

• Additional options (optional)

• Additional key-value pairs (RemoteMessage.data field)

• Sound: true/false
• Expire date (after which it won't be delivered anymore)