gistfile1.m

  // 0. Include the sign in with Google+ button. https://developers.google.com/+/mobile/ios/#sign_in_with_google
  ...

  // 1. Create a |GTLServicePlus| instance to send a request to Google+.
  GTLServicePlus* plusService = [[[GTLServicePlus alloc] init] autorelease];
  plusService.retryEnabled = YES;

  // 2. Set a valid |GTMOAuth2Authentication| object as the authorizer.
  [plusService setAuthorizer:appDelegate.auth];

  // 3. Create a |GTLQuery| object to fetch person data.
  GTLQueryPlus *query = [GTLQueryPlus queryForPeopleGetWithUserId:@"me"];
  
  // 4. Use the "v1" version of the Google+ API.
  plusService.apiVersion = @"v1";
  [plusService executeQuery:query
          completionHandler:^(GTLServiceTicket *ticket,
                              id object,
                              NSError *error) {
              if (error) {
                GTMLoggerError(@"Error: %@", error);
              } else {
                GTMLoggerInfo(@"Fetched your profile data: %@", object);
              }
          }];