Android Push Notification

http://www.androidhive.info/2012/10/android-push-notifications-using-google-cloud-messaging-gcm-php-and-mysql/

https://developers.google.com/android/c2dm/?csw=1

http://www.vogella.com/tutorials/AndroidCloudToDeviceMessaging/article.html

http://developer.android.com/guide/topics/ui/notifiers/notifications.html

http://www.compiletimeerror.com/2013/10/status-bar-notification-example-in.html#.Ut-_hhA1jIU

http://developer.android.com/guide/topics/ui/notifiers/notifications.html#SimpleNotification

http://www.tutorialspoint.com/android/android_notifications.htm

http://www.vogella.com/tutorials/AndroidLifeCycle/article.html