I\'m using the Google .NET API to get analytics data from google analytics.
this is me code to start the authentication:
IAuthorizationCodeFlow flow
There are implementations for Windows 8 applications and Windows Phone available here:
Take a look in the following thread Deploying ASP.NET to Windows Azure cloud, application gives error when running on cloud before you are going to implement your own DataStore.
In the future we might also have a EF DataStore. Remember that it's an open source project so you may implement it and send it to review :) Take a look in our contribution page (https://code.google.com/p/google-api-dotnet-client/wiki/BecomingAContributor)