Firebase Cloud Messaging vs Firebase Realtime Database: What are the differences?

Introduction

Firebase is a powerful development platform that provides various services for building web and mobile applications. Two important services offered by Firebase are Firebase Cloud Messaging (FCM) and Firebase Realtime Database. While both services play crucial roles in Firebase, they have distinct differences in terms of their functionalities and use cases.

1. Scalability:

Firebase Cloud Messaging is primarily designed for sending push notifications to devices, allowing developers to easily engage with users and provide real-time updates. It provides a scalable solution for delivering messages across multiple platforms, including Android, iOS, and web. On the other hand, Firebase Realtime Database focuses on storing and syncing real-time data in a NoSQL cloud database. It provides automatic synchronization and allows multiple clients to access and modify the same data concurrently with offline support.

2. Data Structure:

Firebase Cloud Messaging does not provide a data storage mechanism but is used to send messages to clients based on their registration tokens. It utilizes a key-value pair structure to send custom data payloads along with the notifications. In contrast, Firebase Realtime Database is a JSON-based database that allows developers to store and structure their data hierarchically. This hierarchical structure enables easy querying, indexing, and retrieval of data.

3. Real-time Communication:

Firebase Cloud Messaging enables real-time messaging by delivering messages instantly to connected devices. It allows the app server to trigger notifications to specific devices or topics, making it suitable for real-time chat applications and other similar use cases. Firebase Realtime Database, on the other hand, offers real-time synchronization of data across clients. Any changes made to the data in the database are immediately propagated to all connected clients, ensuring that all clients have the most up-to-date data.

4. Data Persistence:

Firebase Cloud Messaging is focused on message delivery and does not store the data persistently. Once the message is delivered, the FCM server does not retain the data. In contrast, Firebase Realtime Database provides persistent storage for data. It ensures that the data is saved and can be accessed even when the device is offline or the app is closed. Once the device reconnects, the changes made offline are automatically synchronized with the server.

5. Querying and Filtering:

Firebase Cloud Messaging does not offer querying or filtering capabilities on its own as it is primarily used for message delivery. The filtering of messages needs to be implemented on the app server side. On the other hand, Firebase Realtime Database provides powerful querying capabilities to filter and retrieve data based on various criteria. It allows developers to retrieve data based on specific queries, such as filtering by a certain value or ordering the results based on a specific attribute.

6. Integration with Other Firebase Services:

Firebase Cloud Messaging seamlessly integrates with other Firebase services, such as Firebase Authentication and Cloud Functions. It allows developers to trigger push notifications based on user authentication status or provide custom logic when a notification is received. Firebase Realtime Database also integrates with other Firebase services and offers real-time synchronization with them. It can be used in conjunction with Firebase Authentication, Cloud Storage, and Cloud Functions to build robust and scalable applications.

In summary, Firebase Cloud Messaging primarily focuses on push notification delivery, while Firebase Realtime Database is a JSON-based database for storing and synchronizing real-time data. FCM provides scalability for delivering messages, whereas Realtime Database offers real-time communication, data persistence, querying capabilities, and seamless integration with other Firebase services.