android device id confusion

Question

If I dial * # * # 8 2 5 5 # * # * ,

Answer 1

Found on the web:

private static final Uri URI = Uri.parse("content://com.google.android.gsf.gservices");
private static final String ID_KEY = "android_id";

String getAndroidId(Context ctx) {
    String[] params = { ID_KEY };
    Cursor c = ctx.getContentResolver()
            .query(URI, null, null, params, null);

    if (!c.moveToFirst() || c.getColumnCount() < 2)
        return null;

    try {
        return Long.toHexString(Long.parseLong(c.getString(1)));
    } catch (NumberFormatException e) {
        return null;
    }
}

Add permission:

However, I doubt that is a documented ID and I would be carefull because that might not work if GTalk gets updated.

Source: http://blog.codepainters.com/2012/01/17/how-to-obtain-gtalk-android-id/

Also worth having a look at: http://www.toxicbakery.com/android-development/getting-google-auth-sub-tokens-in-your-android-applications/