Facebook Outlines Impacts of Apple's Data Tracking Update

September 27, 2021

What is Happening?


According to Facebook, the platform could be underreporting iOS conversions by 15%:

“Our estimate is that in aggregate we are underreporting iOS web conversions by approximately 15%; however there is a broad range for individual advertisers. We believe that real world conversions, like sales and app installs, are higher than what is being reported for many advertisers.”

It seems like Apple’s controversial App Tracking Transparency (ATT) update is causing significant impacts on Facebook.

Earlier this year Apple launched its new data tracking pop-up alerts, which directly ask iOS users to opt-in to tracking of their activity within each individual app. Based on recent reports, it appears the majority of iOS users are opting out of tracking.

What Does it Mean?


The flow-on effect is that advertisers then have less data to work and that the accuracy of conversion data makes it harder to know what is working.

Big brands are supplementing their Facebook data with data from Google Analytics and other platforms. But it is causing significant impacts, especially for smaller brands who don’t have the analytics capability to cross-check the data from Facebook.


What Can Brands Do:

🧪 Allow time before you analyse performance:

Advertisers need to give its systems time to adapt before making changes to underperforming campaigns. “Given the nuances of delayed data and modeled reporting, consider waiting a minimum of 72 hours or the full length of the optimization window selected before evaluating performance for conversion-optimized campaigns.”

👷 Follow learning phase best practices:

Facebook’s ‘Learning Phase’ best practices suggest that it takes around 50 optimization events within a 7-day period for Facebook’s ad matching systems to get a full view of best response to your ad, which will then help Facebook optimize ad delivery moving forward.

⚙ Set up the Conversions API

Facebook’s Conversions API helps create direct connection between website events and Facebook, which can also mitigate the impacts of ATT. “Adding the Conversions API to your existing setup will help you optimize your ad campaigns, decrease cost per action and more accurately measure campaign outcomes while offering the same privacy protections we’ve put in place across our other Business Tools”.