Atmosphere vs io.js: What are the differences?

Atmosphere: Realtime Client Server Framework for the JVM, supporting WebSockets and Cross-Browser Fallbacks Support. The Atmosphere Framework contains client and server side components for building Asynchronous Web Applications. The majority of popular frameworks are either supporting Atmosphere or supported natively by the framework. The Atmosphere Framework supports all major Browsers and Servers; io.js: A friendly fork of Node.js with an open governance model. io.js is a JavaScript platform built on Chrome's V8 runtime. This project began as a fork of Joyent's Node.js and is compatible with the npm ecosystem.

Atmosphere and io.js belong to "Frameworks (Full Stack)" category of the tech stack.

"Cross-Browse" is the primary reason why developers consider Atmosphere over the competitors, whereas "Compatible with NPM" was stated as the key factor in picking io.js.

Atmosphere is an open source tool with 3.34K GitHub stars and 720 GitHub forks. Here's a link to Atmosphere's open source repository on GitHub.