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.
With Parse, you can add a scalable and powerful backend in minutes and launch a full-featured app in record time without ever worrying about server management. We offer push notifications, social integration, data storage, and the ability to add rich custom logic to your app’s backend with Cloud Code.
Appcelerator is the first mobile platform to combine the flexibility of open source development technologies with the power of cloud services.
DreamFactory is an open source REST API backend for mobile, web, and IoT applications. It provides RESTful web services with pre-built connectors to SQL, NoSQL, file storage systems, and web services. It's secure, reusable, and offers live API documentation.