Firebase vs Google Cloud Messaging: What are the differences?

Firebase: The Realtime App Platform. Firebase is a cloud service designed to power real-time, collaborative applications. Simply add the Firebase library to your application to gain access to a shared data structure; any changes you make to that data are automatically synchronized with the Firebase cloud and with other clients within milliseconds; Google Cloud Messaging: Simple and reliable messaging to reach over a billion devices. Google Cloud Messaging (GCM) is a free service that enables developers to send messages between servers and client apps. This includes downstream messages from servers to client apps, and upstream messages from client apps to servers.

Firebase and Google Cloud Messaging are primarily classified as "Realtime Backend / API" and "Mobile Push Messaging" tools respectively.

Some of the features offered by Firebase are:

• Add the Firebase library to your app and get access to a shared data structure. Any changes made to that data are automatically synchronized with the Firebase cloud and with other clients within milliseconds.
• Firebase apps can be written entirely with client-side code, update in real-time out-of-the-box, interoperate well with existing services, scale automatically, and provide strong data security.
• Data Accessibility- Data is stored as JSON in Firebase. Every piece of data has its own URL which can be used in Firebase's client libraries and as a REST endpoint. These URLs can also be entered into a browser to view the data and watch it update in real-time.

On the other hand, Google Cloud Messaging provides the following key features:

• Versatile Messaging Targets: Distribute messages to your client app in any of three ways — to single devices, to groups of devices, or to devices subscribed to topics.
• Downstream Messaging: For purposes such as alerting users, chat messaging or kicking off background processing before the user opens the client app, GCM provides a reliable and battery-efficient connection between your server and devices.
• Upstream Messaging: Send acknowledgments, chats, and other messages from devices back to your server over GCM’s reliable and battery-efficient connection channel.

"Realtime backend made easy" is the primary reason why developers consider Firebase over the competitors, whereas "Free" was stated as the key factor in picking Google Cloud Messaging.

Instacart, 9GAG, and Twitch are some of the popular companies that use Firebase, whereas Google Cloud Messaging is used by paytm, Ressy Technologies Private Limited, and Life360. Firebase has a broader approval, being mentioned in 859 company stacks & 997 developers stacks; compared to Google Cloud Messaging, which is listed in 18 company stacks and 8 developer stacks.