How to call https://www.googleapis.com/plus/v1/people/me at google

I am developing an Android application and need to get the "me" info from google but I always ends up in either response code 401 or 403. What am I doing wrong? Here is my code:

private static final String GOOGLE_AUTH_TOKEN_TYPE = "oauth2:https://www.googleapis.com/auth/plus.me";

I get the oauth token by (note...code below is shortened):

Account googleAccount = (AccountManager) getSystemService(ACCOUNT_SERVICE).getAccountsByType("com.google")[0];
final Bundle bundle = manager.getAuthToken(googleAccount, GOOGLE_AUTH_TOKEN_TYPE, true, null, null).getResult();
String authToken = bundle.getString(AccountManager.KEY_AUTHTOKEN);

So far so good... I now have a token so everything looks good here.

Now get the me info:

String GOOGLE_ME_URL = "https://www.googleapis.com/plus/v1/people/me";
final DefaultHttpClient client = new DefaultHttpClient();
final HttpGet request = new HttpGet(GOOGLE_ME_URL);
request.addHeader("Authorization", "OAuth=" + authToken);
final HttpResponse response = client.execute(request);

This gives response code 401.

I have also tried:

final DefaultHttpClient client = new DefaultHttpClient();
final HttpGet request = new HttpGet(GOOGLE_ME_URL + "?access_token=" + authToken);
final HttpResponse response = client.execute(request);

This gives response code 403 - Something like "Daily limit exceeded. Please sign up".

What am I doing wrong? what have I missed? How should this be done?

Thanks

// Edits below Some more investigation: I added a project into code.google.com/apis/console and took the key generated from there and put into the url, like: https://www.googleapis.com/plus/v1/people/me?key=my_generated_key&access_token=" + authToken. Now the call works fine and I