What are some alternatives?
When comparing Wise Notifications and Airflow, you can also consider the following products
PushAlert - PushAlert allows you to send push notifications to your website subscribers on Chrome, Firefox and Safari. Signup for free and send unlimited notifications.
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
PushOwl - Re-engage website visitors with push notifications
Pipefy - The new development platform built for agile teams.
PushEngage - Personalized Browser Push Notifications.
Pushwoosh - Push Notifications Service | Your Apps Can Talk!