Pushover - Real-time notifications on your Android, iPhone, iPad, and Desktop
Pushbullet - Pushbullet - Your devices working better together
DeviceConsole - Progressiv Web App that allow you to register many devices linked to one Google account and push...
AirDroid - Access Android phone/tablet from computer remotely and securely. Manage SMS, files, photos and videos, WhatsApp, Line, WeChat and more on computer.
Amazon SNS - Fully managed pub/sub messaging for microservices, distributed systems, and serverless applications
Gotify - a simple self-hosted server for sending and receiving messages