Currently, ITP is only enabled for mobile and desktop versions of Safari. According to Statcounter as of August 2017, Safari holds a little over 20% of the desktop browser market – but as much as 58% of the iPad tablet market (Android mobile devices do not support Safari). This may not sound like much compared to Firefox or Chrome, but it actually represents millions of users. And, as privacy concerns grow, advertisers and marketers alike can expect this type of technology to spread across all popular browsers and devices.

To help with these changes, Google Analytics has created a new type of cookie, called _gac, which extends Google Analytics tracking to include AdWords conversions. Whenever auto-tagging is enabled, the cookie is used to store ad click details. Right now, the cookie is sent from Googleadservices.com — which makes it a third-party cookie and one of the types that Apple’s machine learning process would in turn segment and separate.

If you’re working with a vendor that uses its own form of reporting and measurement, ask them what steps they have put into place to mitigate the issues arising from potentially lower data quality from Safari users. It’s important to note that there will likely be shifts and changes in the performance data that’s gathered in the coming weeks and months — so avoid any rash decisions for the time being until things settle.