title: How to get gmail user's contacts?
body: <p>I need to retrieve the email addresses that the user has stored in his gmail account. In my app, the user can now decide to invite a friend of him. I want that the application (if the user tell me "ok") presents a list of the user's contacts email addresses stored in gmail, among which he can choose one or more...</p>
  
  <p>I know that exists <a href="http://code.google.com/intl/it-IT/apis/accounts/" rel="noreferrer">Authentication and Authorization for Google APIs"</a>. Is it the right way? And, how to use them in Android?</p>