IntelliJ IDEA - Capable and Ergonomic IDE for JVM
Socket.io - Realtime application framework (Node.JS server)
SignalR - SignalR is a server-side software system designed for writing scalable Internet applications, notably web servers.
vert.x - From Wikipedia, the free encyclopedia
Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Lightstreamer - Lightstreamer is a server for delivering real-time messages to browser-based and mobile...