Pushover

Description

Pushover is a simple push notification service that integrates easily into web apps like IFTTT, network monitoring systems like Nagios, shell scripts, servers, and anything else that needs to send alerts to your Android, iPhone, iPad, and Desktop.
Now includes home-screen and lock-screen widgets for Android 4.0+, support for sending notifications to Pebble watches, a DashClock extension, and a Tasker event plugin!
Visit https://pushover.net/ to find apps, plugins, and services that support Pushover, or get a free API key to create your own app.