Pusher

Hosted real-time messaging and push notifications.

Pusher Channels provides a hosted WebSocket infrastructure that simplifies adding real-time functionality to web and mobile applications. It abstracts away the complexity of maintaining persistent connections, auto-scaling, and protocol fallbacks behind a simple publish-subscribe API organized around named channels and typed events. Presence channels track who is online in real time, while client events let users broadcast directly to channel subscribers without server roundtrips. Webhooks provide server-side notifications for channel lifecycle events. Pusher client SDKs are available for JavaScript, iOS, Android, Python, PHP, and many more platforms. Its global infrastructure handles billions of messages daily and is trusted by companies like GitHub, Mailchimp, and the Financial Times.