code: public static void login(final String token, final LoginCallback callback) {
  		if (StringUtils.isNullOrEmpty(token)) {
  			throw new IllegalArgumentException("Token is null or empty");
  		}
  
  		dispatchOnConversationQueue(new DispatchTask() {
  			@Override
  			protected void execute() {
  				try {
  					loginGuarded(token, callback);
  				} catch (Exception e) {
  					ApptentiveLog.e(CONVERSATION, e, "Exception while trying to login");
  					logException(e);
  
  					notifyFailure(callback, "Exception while trying to login");
  				}
  			}
  		});
  	}
docs: Starts login process asynchronously. This call returns immediately. Using this method requires
  you to implement JWT generation on your server. Please read about it in Apptentive's Android
  Integration Reference Guide.
  
  @param token    A JWT signed by your server using the secret from your app's Apptentive settings.
  @param callback A LoginCallback, which will be called asynchronously when the login succeeds
  or fails.