Google Cloud Messaging for Android (GCM) is a service that helps you to send data from your server to your users’ Android-powered device. Apart from that you can even receive messages from devices on the same connection. The best part is that you can avail this service free of cost. It doesn’t matter how big your message is. For example you can send a message that contains up to 4kb of payload data or even a movie. It offers a send-to-sync feature which alerts you when you receive a new email on the server.
GCM even maps a single user to a notification key, which you can then use to send a single message to multiple devices owned by the user. This service was debuted last year and attained great popularity over the past one year. It has made the lives of many people easier like never before. Presently about 60% of the top 100 apps in the Google Play store are using Cloud Messaging Service. About 200,000 push messages are sent in a second.
During the Google I/O conference held in San Francisco, Google Cloud Messaging was made to be a part of Google Play Services. Google will also introduce three new features to this service. First of all it has included “persistent connections,” that helps you to push out messages quickly. Secondly, upstream messaging feature that allows to send data from your app to your servers. Lastly, synced notifications across devices for example, if you have an email application.
When a user receives new email on the server, the server pings the mobile application with a “New mail” message. This tells the application to sync to the server inorder to check the new email. Mountain View has recently announced that Cloud Messaging can now be accessed to all versions of Chrome and Chrome OS.
“GCM now supports connections between a persistent connection from servers to many devices as quickly as possible,” a Google spokesperson told attendees. “It is also launching upstream messaging to send data in the other direction — from the app to servers.”
It also is launching a new API that syncs notifications across devices.
“All of the new features are rolling out progressively, and all you have to do up is sign up starting today,” he added.
You can take a look at the following video to see what was mentioned about Google Cloud Messaging in the Google I/O conference.