Q:

Is Firebase Cloud Messaging free for unlimited mobile user?

My project already have developed mobile application (hybrid using Cordova). Now we want to support a push notification for Android and iOS. We are planning to support push notification using Firebase Cloud Messaging (FCM). Idea is that our mobile app will be registered with FCM and we will use FCM to send push notifications to (read unlimited) mobile devices.
As per many site, FCM is free for push notification, but I did not see clear guideline by FCM sites.
Additionally FCM pricing model also says that 100 real database connections are free and after that you need pay as per licensing model.
Refer : https://firebase.google.com/pricing/
Question is, do I need a real database connection with FCM if I am interested only in push notification feature? Is push notification feature of FCM is free for unlimited mobile devices connected to same mobile application?
If anybody have official document on this, please share.

A:

Firebase Cloud Messaging is a free Push Notification service (previous version known as Google Cloud Messaging).

Do I need a real database connection with FCM if I am interested only in push notification feature?

No. FCM is a separate service from Firebase Realtime Database.

Is push notification feature of FCM is free for unlimited mobile devices connected to same mobile application?

Like I mentioned initially, the FCM service is included free for any Firebase Plan. The Pricing documentation already shows this:

Included Free
Analytics, App Indexing, Authentication, Cloud Messaging, Crash Reporting, Dynamic Links, Invites, Notifications & Remote Config

And yes. There is no limit to the number of users you plan to connect using FCM. See my answer here.

