Pushover - Real-time notifications on your Android, iPhone, iPad, and Desktop
IBM BigFix - Endpoint Management
Pushbullet - Pushbullet - Your devices working better together
Jamf Endpoint protection - Jamf Endpoint protection is an all-in-one endpoint security providing a utility that is designed for the macOS system.
Gotify - a simple self-hosted server for sending and receiving messages
Hexnode MDM - Mobile Device Management solution from Hexnode helps you monitor, manage and secure mobile devices across your organization.