Radar vs Syncano: What are the differences?
Radar: High level API and backend for writing web apps that use push messaging. Radar is built on top of engine.io, the next-generation backend for socket.io. It uses Redis for backend storage, though the assumption is that this is only for storing currently active data; Syncano: a highly flexible real-time backend as a service. Syncano is a backend platform to build powerful real-time apps more efficiently. Integrate with any API, minimize boilerplate code and control your data - all from one place.
Radar and Syncano belong to "Realtime Backend / API" category of the tech stack.
Radar is an open source tool with 209 GitHub stars and 35 GitHub forks. Here's a link to Radar's open source repository on GitHub.