Background

This application was originally written while reading the documentation for C2DM, as a practical step-by-step to getting a working standalone implementation. My primary goal was to create a scenario wherein I could tell an application server to send a message to user X, and it would broadcast that message to all of that user's registered devices.

Configuring this application

Look in res/values/config.xml to adjust the C2DM sender address and your server's C2DM registration URL. The sender address you configure must be registered for C2DM; it does not necessarily have to be the same Google Account used to release the application to the Market. Requests to the C2DM registration URL will be via the POST method, with the URL-encoded parameters registration_id and device_id (for C2DM) or user_id and device_id (for correlation).

See the c2dm-web project for a reference implementation of this server.

What this application does

This application does three things:

1. It obtains a C2DM registration ID, which it then sends to your server at the configured C2DM registration URL along with the device ID.
2. It contains an activity that demonstrates how one can register the device ID with a user ID for convenience.
3. It displays a status bar notification whenever the device receives a C2DM message from your server.