Blockbutler - Real-time transaction notifications for the blockchain
Coinzy - Top need-to-know crypto news in less than 8 minutes a day
Notif.me SDK - A Node.js lib to send all your transactional notifications
Coinwink - Crypto alerts, watchlist and portfolio tracking app for Bitcoin, Ethereum, and other 3500+ crypto coins and tokens
Pusher - Pusher is a hosted API for quickly, easily and securely adding scalable realtime functionality via WebSockets to web and mobile apps.
Coin Demo - Visual demonstration of how bitcoin transactions work