private void logUser() {
   // TODO: Use the current user's information
   // You can call any combination of these three methods
   Crashlytics.setUserIdentifier("12345");
   Crashlytics.setUserEmail("*****@*****.**");
   Crashlytics.setUserName("Test User");
 }
 @Override
 public void call(JSONArray args) throws JSONException {
   Crashlytics.setUserEmail(args.getString(0));
 }