Heroku's app webhooks offering is now generally available for all Heroku users. App webhooks allows users to automatically send notifications to developers in the event of specified occurrences. Whether communication is through a bot, dashboard, or otherwise, app webhooks can power communications.
Pusher has released Beams, a push notifications API for mobile app developers. Pusher Beams allows developers to manage device tokens for iOS and Android apps. Developers can also use Beams to trigger notifications based on the in-app activity of users so that users remain engaged with their apps.