CleverTap
Drive Customer Engagement with personalized Push Notifications across Mobile, Web and in-app

Use CleverTap to send personalized, rich-media push notifications that keep users hooked on your app.
CleverTap is an All-In-One customer engagement platform that unifies interactions between people, processes and technology. CleverTap is built to convert customers into customers for life with in-moment experiences designed and optimized for scale, in real-time. We enable brands to create truly cross-channel experience, transcending boundaries between channels, journeys and outcomes. We’re on a mission to be the ultimate growth partner, providing businesses with the insights they need to truly understand their customers and deliver.
OneSignal
https://onesignal.com/

Re-engage Customers with Real-Time Web Push Notifications
Build stronger, more valuable customer relationships with desktop and browser notifications.
OneSignal now empowers over a million businesses to send 12 billion messages daily. One in every five apps now chooses OneSignal. And we’re still working hard to democratize customer engagement because we believe that businesses of all sizes should have access to the tools they need to thrive.
PushAlert
https://pushalert.co/

Push Notification for Website, No Mobile App Required.
Increase reach, revenue, re-target users with Web Push Notifications on desktop and mobile.