What is your experience in implementing and integrating push notifications in applications?

In my experience implementing push notifications in Flutter applications, I used Firebase Cloud Messaging (FCM). For integration, I added the necessary dependencies to pubspec.yaml, configured the project in Firebase Console, and then implemented handling of receiving notifications both in the background and in the active state of the app.

Example of FCM setup in Flutter:

import 'package:firebase_messaging/firebase_messaging.dart';

final FirebaseMessaging _firebaseMessaging = FirebaseMessaging.instance;

void setupFCM() async {
  NotificationSettings settings = await _firebaseMessaging.requestPermission();

  if (settings.authorizationStatus == AuthorizationStatus.authorized) {
    String? token = await _firebaseMessaging.getToken();
    print('FCM Token: $token');

    FirebaseMessaging.onMessage.listen((RemoteMessage message) {
      print('Received a message while in the foreground: ${message.messageId}');
      // Handle notification
    });
  }
}

I also integrated the server part for sending notifications via the FCM API.