Uniqush
Uniqush is a free and open source software system
...By running Uniqush on the server side, you can send push notifications to any supported mobile platform. Stand-alone server program dedicated to push service, which means you can run it on your own server. Multiple platforms are supported for popular smart phone systems including android, iOS, etc. And we will support more in the future. Simple and unified interface for Apps’ server developers. You don’t need to care about the receiver’s system, simply send an HTTP request to Uniqush server and it will do all things for you. No need to implement re-send on failure mechanisms, Uniqush will re-send the notification on a recoverable error whenever possible.