Using Android's C2DM with market disabled

I am developing an Android app as a research tool. The idea behind is that a researcher hands out a couple of Android device to participants and they use the device to gather data on behalf of the researcher.

Now I would like to make use of Android's C2DM (cloud to device messaging). The problem here is that a Google account is required. This is not going to work f开发者_JAVA技巧or me since the researcher would have to pre-configure one account for each device. That would be feasible but the actual problem arises from the Market access. Participants could use that account to buy anything from the Market. So my question is how to limit the Market's functionality to just free apps while maintaining C2DM.

Thanks everyone

You cannot "limit the Market's functionality to just free apps".

You could seek an alternative solution for your problem, other than C2DM. There are third party options, such as Urban Airship, that probably do not require Google accounts.

Or, you could root the devices and try to remove the Market application entirely, along with any other application that might depend on that account (e.g., Gmail, Dialtacts). However, there is a decent chance that you will miss something.

You might be able to root the devices and block access to the market address - C2DM would continue to function but the market itself would cease to function.