Adding Secure Publishing To The PubNub Realtime Messaging Workflow. PubNub ★ Push Real-time Data to Mobile, Tablet, Web. Beaconpush - push service for creating real-time web apps using HTML5 WebSockets and Comet. Pusher | HTML5 WebSocket Powered Realtime Messaging Service. Urban Airship - Powering Push Notifications, In-App Purchase, and Subscriptions for mobile applications across major mobile platforms. Superfeedr : Real-time feed parsing in the cloud - Atom over PubSubHubbub and XMPP.