I want to send one common message say "Happy new year" through C2DM to more than one registered device. I have got few ideas about C2DM from the link http://code.google.com/android/c2dm/index.html and understood that each devices registered for C2DM they have different auth token and registration id. So is it possible for the third application server to send the same message to all the devices registered with. I am using the sample code for Chrome to phone downloaded from http://code.google.com/p/chrometophone/source/checkout.
So any help from any one would be appreciated.
To be clear, the devices don't have authentication tokens. Your application server uses the ClientLogin auth token to authenticate with C2DM for sending pushes. During registration, each device receives a registration ID which it communicates to the application server.
At the moment, C2DM does not support batch sending. You will have to iterate through your devices and send each one of them the same message.
See this thread for details.