使用Google App Engine在Android中推送通知

I am currently developing an app where users create posts that are stored on a server. When another user shows interest in a post by clicking a button, I want to notify the author of the post using push notifications. I have already set up the data storage using cloud endpoints with Google App Engine. Is there anyway I can use these endpoints to implement push notifications? If not is there another easy way to implement push notifications given my current setup? I have already read about Google Cloud Messaging on the developers page but was somewhat confused. I have kept track of the registration id's but I don't really know where to go from there. Thanks in advance.I am currently developing an app where users cr