Notif.me SDK - A Node.js lib to send all your transactional notifications
Pusher Beams - Send push notifications programmatically at scale
Ethereum Push Notification Service - Protocol for incentivized, blockchain based notifications.
Push Notification Preview - A simple tool for previewing push notification copy
Blockbutler - Real-time transaction notifications for the blockchain
Ultimate Push Notifications by Ecomfit - Retarget customers and protect abandoned cart to boost sale