Reaching users.
WHAT IT PROVIDES
Sending notifications and data messages to devices across platforms.
WHAT YOU NEED
A registration token per device installation Server-side code to send Handling for tokens that change
WHY TOKENS CHANGE
Reinstallation, restoration to a new device, and periodic refresh.
WHAT TO DO
Refresh and re-register, and remove tokens that are rejected.
WHAT TOPICS PROVIDE
Sending to everyone subscribed to a topic, without maintaining lists.
WHAT TO BE CAREFUL WITH
Topics anyone can subscribe to from the client.
WHY
A user can subscribe to a topic intended for others.
WHAT TO DO FOR SENSITIVE AUDIENCES
Manage subscription server-side.
WHAT PERMISSION IS REQUIRED
Explicit permission on both platforms.
WHEN TO ASK
After demonstrating why notifications are useful.
WHAT TO NEVER INCLUDE
Sensitive content, which appears on a locked screen.
WHAT TO PROVIDE
Granular preferences, so users disable categories rather than everything.
WHAT TO MONITOR
Delivery and open rates, and unsubscribes.
