ejabberd is World's Most Popular XMPP ServerIt leads in many areas:
ejabberd mobile reliability layer helps manage mobile network’s disconnection, message deliveries, consistent conversation on any online device, push notification and mobile interfaces.
All the modules that deal with performance and scalability have been rewritten. This rewriting saves 50% of memory and uses less CPU. In other words, ejabberd manages 50% more end users using the same hardware!
ejabberd supports more interaction with the browser and the web app, facilitating real-time messaging. The use of WebSockets provides the ability to seamlessly send and receive messages while a browser tab is opened. BOSH capability is provided as a fallback for XMPP connections.
Now all ejabberd main features like mobile reliability features for instance are accessible from any mobile app or webpage thanks to API interfaces. ejabberd provides libraries, for web pages and mobile apps, to be easily integrated within your own source code.