FCM ID vs FCM Token vs APNS Token

Question

I'm trying to send notification to specific users on my cordova application using cordova-plugin-firebasex which is a fork of cordova-plugin-firebase with fixs and improvement.

I'd like to know what are the differences between FCM Id, FCM Token, and APNS Token, since there is no accurate explication on this.

Also, which one should you use to send push notifications to specifics users, for both Android & iOS.

Depraved

Answer 1

The notifications are divided in two components:

• The device token (APNs) and the Device ID (FCM).
• Payload

Within these two components we find various differences:

• FCM is sent as JSON payloads and APNS sends either string or dict.
• FCM has a payload of 2KB while APNS has a payload of 4KB.
• APNS saves 1 notification per App while FCM saves 100 notifications per device.
• FCM supports multiple platforms while APNS requires of their proprietary platform.
• Acknowledgement can be sent in FCM if using XMPP, but it's not possible on APNS.

Disapprobation

Can you please add some clarity to this statement and maybe a reference? Acknowledgement can be sent in FCM if using XMPP, but it's not possible on APNS. – Loupe

firebase.google.com/docs/cloud-messaging/xmpp-server-ref @Loupe – Disapprobation