At the moment, Gitt only supports Facebook, Twitter, Google AdWords, LinkedIn or AdRoll pixel tracking.
What is a Pixel Tracking?
Ad platforms such as Facebook and Adwords provide a conversion tracking tool to allow you to gather data on your customers and how they behave on your website. By adding your pixel ID from either of the platforms, you will be able to optimize marketing simply by using short URLs.
Please keep in mind, this is a Pro features which will require you to get a valid subscription.
UPDATE: We added more information about how to get your tracking ID head over on the settings page of this feature.