When do you need to track activity across multiple domains?

You will need to use cross-domain tracking if you want to aggregate visits on multiple domains into one single session and you want to attribute the conversion to the initial touch point via a postback URL. If one of the domains is not under your control, you probably want to track it using one of the native integrations found under the integration catalog.

Popular Use Cases for Cross-domain Tracking 

• When articles from your blog promote products sold on your Shopify / WooCommerce site.
• When your tracking funnel including a quiz on a third-party service

A real life example

Your visitors click on a Facebook Ad and visits your landing page. Using the atclid param you forward the client to your Shopify store and the client bought a watch on your store. Once the purchase is made, you will see that the users came from the Facebook campaign and you will have Facebook click id attributed for that user.

Please note that AnyTrack will not sync back the conversion on the landing page property and you will see that on the last website the user made the purchase on. Learn more on that in this article.