Apache Spark is a fast cluster computing system supporting interactive queries with SQL, machine learning, and graph computation all handled through the Spark API. The Apache Spark Java Library enables developers to quickly write programs in Java that access a unified engine in order to process large amounts of data. Supported by the Apache Software Foundation, the Java library comes well documented.
Firebase, real-time backend for web application development, originally launched a little over a year ago. Since its launch, Firebase has remained in beta while it continued to improve its service and build a customer base. Over the past year, Firebase has added features, functionality, and thousands of customers. Accordingly, Firebase has announced it is leaving its beta stages behind and publically launching as a full-fledged paid product.