Ethereum Push Notification Service - Protocol for incentivized, blockchain based notifications.
Coinzy - Top need-to-know crypto news in less than 8 minutes a day
Blockbutler - Real-time transaction notifications for the blockchain
Crypti - A minimal cross-platform Bitcoin price widget
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