With Google, I do an initial check after the purchase to ensure the product is licensed, and then I check back a couple of weeks later to ensure that a refund wasn't issued. I cache all of the license information after that, so Wi-fi is not needed again. Google provides access to their license servers, but I ultimately have control over how to process that information.
With Amazon, the DRM model they provide requires that users periodically log in to the Amazon App Store to refresh the application licenses. So this means that users who purchase off Amazon will have to make sure that they log in to the Amazon App Store every couple weeks or so. I do not have control over this licensing process, as Amazon injects this check into the APK itself. The only option Amazon gives me is no DRM at all, meaning I'm not protected from piracy at all (which is pretty rampant on Android) or to use their DRM. If I knew how to set up my own licensing server, I would consider doing that instead...
Mike
With Amazon, the DRM model they provide requires that users periodically log in to the Amazon App Store to refresh the application licenses. So this means that users who purchase off Amazon will have to make sure that they log in to the Amazon App Store every couple weeks or so. I do not have control over this licensing process, as Amazon injects this check into the APK itself. The only option Amazon gives me is no DRM at all, meaning I'm not protected from piracy at all (which is pretty rampant on Android) or to use their DRM. If I knew how to set up my own licensing server, I would consider doing that instead...
Mike