Firebase vs Google App Engine: What are the differences?

What is 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.

What is Google App Engine? Build web applications on the same scalable systems that power Google applications. Google has a reputation for highly reliable, high performance infrastructure. With App Engine you can take advantage of the 10 years of knowledge Google has in running massively scalable, performance driven systems. App Engine applications are easy to build, easy to maintain, and easy to scale as your traffic and data storage needs grow.

Firebase belongs to "Realtime Backend / API" category of the tech stack, while Google App Engine can be primarily classified under "Platform as a Service".

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 App Engine provides the following key features:

• Zero to sixty: Scale your app automatically without worrying about managing machines.
• Supercharged APIs: Supercharge your app with services such as Task Queue, XMPP, and Cloud SQL, all powered by the same infrastructure that powers the Google services you use every day.
• You're in control: Manage your application with a simple, web-based dashboard allowing you to customize your app's performance.

"Realtime backend made easy", "Fast and responsive" and "Easy setup" are the key factors why developers consider Firebase; whereas "Easy to deploy", "Auto scaling" and "Good free plan" are the primary reasons why Google App Engine is favored.

Instacart, 9GAG, and Twitch are some of the popular companies that use Firebase, whereas Google App Engine is used by Snapchat, Movielala, and Wix. Firebase has a broader approval, being mentioned in 859 company stacks & 992 developers stacks; compared to Google App Engine, which is listed in 481 company stacks and 343 developer stacks.