simperium - Move data everywhere it's needed, instantly and automatically
Socket.io - Realtime application framework (Node.JS server)
GUN - Self-hosted Firebase.
SocketCluster - An open, scalable realtime engine for Node.js
PubNub - PubNub is a real-time messaging system for web and mobile apps that can handle API for all platforms and push messages to any device anywhere in the world in a fraction of a second without having to worry about proxies, firewalls or mobile drop-offs.
Primus - Primus, the creator god of the transformers & an abstraction layer for real-time to prevent...