How to Enable Push Notifications
Read moreCan firebase send push notifications iOS?
For Apple client apps, you can receive notification and data payloads up to 4000 bytes over the Firebase Cloud Messaging APNs interface . To write your client code in Objective-C or Swift, we recommend that you use the FIRMessaging API.
Read moreDo push notifications work when app is closed iOS?
Apple does not offer a way to handle a notification that arrives when your app is closed (i.e. when the user has fully quit the application or the OS had decided to kill it while it is in the background). If this happens, the only way to handle the notification is to wait until it is opened by the user.
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