I am programming a iOS and Android app with Firebase. Now I want to implement Push Notifications. That works fine so far. I want that when a user interacts with another in a certain action one user is getting notified via a push notification.
Now my question is how can I achieve this, I am saving the FCM token in my users collections. I thought I could use the FCM API but then I need the Bearer token can I save something like this in the app or do I need to write my own backend for this?
And thoughts on this, maybe I am missing something. I know there are Cloud Functions but I can't use them because then the project needed to be a Blaze project. The problem is, that I don't want surprise bills from firebase since this is a hobby project.