Google is implementing a new DRM program for the Android Marketplace which will use a licensing server to verify a user has purchased the app before it launches.
Apps can be written to handle the interaction with the licensing server in any way the developer choose, but Google is providing two preconfigured implementations that will stop an app from running if the server doesn't or can't verify the app's license. The second method will only allow the app to start if the server is available to verify the license.