I'm on Galaxy S III with Android 4.0.4, Google Play installed.
In my app I try to get a token from the Google Play services, as described on https://developers.google.com/android/google-play-services/authentication. Since it's all quite new (the Google pages were last updated this week), there's not much documentation to be found, especially about each specific error code.
final String token = GoogleAuthUtil.getToken(this, "
[email protected]", "scope");
gives me an exception:
09-30 11:24:36.075: ERROR/GoogleAuthUtil(11984): GooglePlayServices not available due to error 1
09-30 11:24:36.105: ERROR/AuthTokenCheck_(11984): Error 1
        com.google.android.gms.auth.GooglePlayServicesAvailabilityException: GooglePlayServicesNotAvailable
        at com.google.android.gms.auth.GoogleAuthUtil.f(Unknown Source)
        at com.google.android.gms.auth.GoogleAuthUtil.getToken(Unknown Source)
        at com.google.android.gms.auth.GoogleAuthUtil.getToken(Unknown Source)
        at mobi.app.activity.AuthTokenCheck.getAndUseAuthTokenBlocking(AuthTokenCheck.java:148)
        at mobi.app.activity.AuthTokenCheck$1.doInBackground(AuthTokenCheck.java:61)
        at android.os.AsyncTask$2.call(AsyncTask.java:264)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
        at java.util.concurrent.FutureTask.run(FutureTask.java:137)
        at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
        at java.lang.Thread.run(Thread.java:856)
https://developers.google.com/android/google-play-services/reference/com/google/android/gms/auth/package-summary tells me:
  GooglePlayServicesAvailabilityExceptions are special instances of
  UserRecoverableAuthExceptions which are thrown when the expected
  Google Play services app is not available for some reason.
But what exactly does that mean? And how to resolve it? I've added the Google Play services extras in my SDK and the jar to my project, marked as 'exported'.
I'm also wondering what the "Google Play services app" exactly is. Unfortunately it's all not very clearly described at https://developers.google.com/android/google-play-services/.
  The Google Play services component is delivered as an APK through the
  Google Play Store, so updates to Google Play services are not
  dependent on carrier or OEM system image updates. Newer devices will
  also have Google Play services as part of the device's system image,
  but updates are still pushed to these newer devices through the Google
  Play Store.
Isn't "Google Play services" app the same as the "Google Play" app?
Another question I have, due to lack of documentation: what is the scope parameter for?
The documentation just says the following, but not defining what an '
authentication scope' exactly is:
scope   String representing the 
authentication scope.