URBNG-207 first version of Android WebServerInterface.

I have several questions regarding the first version of the WebServerInterface class. I would appreciate if reviewer addressed them:

1) what's the most comfortable way for client to use WebServerInterface class ? Currently listener pattern has been implemented. 
2) For each method of WebServerInterface class user must implement corresponding interface, which callback will be called after query has completed. Is it good solution (one method <-> one interface with callback), or is there better approach ?
3) I would like to create separate, custom AsyncTask for each query method (for example there is AsyncGetGameInfo class for getUrbanGameInfo() method). Is it good idea ?

I would also like to get feedback about WebServerInterfaceTest class.

Thank you for your time.