Appsumer, an InMobi company that provides automated reporting to performance marketing teams, released data this week that analyzes the impact of Apple’s App Tracking Transparency (ATT) on larger and smaller advertisers.

This report takes a close look at the impact of Apple’s privacy changes.

One of the more surprising findings is that larger, more sophisticated advertisers have been able to maintain or even increase their iOS spending a year after ATT launched. Smaller advertisers continue to struggle with the amount spent on iOS.  

“One assumption might be that a lot of the iOS share of wallet would go to Android, so it was interesting to see that larger advertisers increased their share of spend on iOS,” says Appsumer General Manager Shumel Lais. “We also found that smaller advertisers were still trying to come to grips with the changes, even a year later.”

Smaller advertisers saw their iOS share of spend drop from 41% pre-ATT in Q1 2021 to 35% post-ATT in Q1 2022.

Some 31% of publishers with 100,000 or more daily active users (DAU) shifted spend from iOS to Google Android, compared with 16% of those with less than 100,000 DAUs.

About 12% of larger publishers reduced iOS spending, but Android spending remained the same compared with 20% of those with more than 100,000 DAUs.

The companies that have resources in-house such as predictive modeling did better during the past year compared with those that do not. Divesting media buys in a variety of channels, rather than making all their investments in channels like Facebook, also helped, Lais says.

Identifying the optimal Conversion Value setup and Conversion Window length on SKAN remains one of the main challenges Appsumer identified in the past year for performance advertisers.

Conversion Values are a 6-bit code — six 0s or 1s — included in the SKAN postback that creates up to 64 combinations of post-install conversion events that marketers can track.

They are designed to highlight the value of an app install by identifying conversion events that occur, such as a purchase, ad impression, trial signup, according to the report titled Apple’s privacy changes one year on: The good, the bad and the solutions.

There are several approaches to Conversion Values based on the monetization model of an app and what the mobile measurement partner (MMP) offers.

In addition, there is also a Conversion Window — the time in which advertiser decides to leave between the install and the SKAN postback being sent.

One postback is sent for each install, and the minimum length is 24 hours. There is no change in the Conversion Value for 24 hours when it is automatically returned.

Meta previously dictated that advertisers on its platforms needed to set this window to 24 hours, but has since changed course.

The report points to other major challenges. In addition to the fact that testing on iOS is increasingly limited, SKAN is Apple’s mysterious privacy threshold. It returns a “’NULL’ Conversion Value and source app details when a specific volume of installs isn’t met for a campaign,” the report says. Then there are duplicate installs across different attribution sources.

On iOS version 14.5 and more recent versions, after an install occurs, SKAdNetwork immediately starts tracking and attributing them. Simultaneously, an ATT prompt will be shown during the onboarding flow and the user may opt in to share their IDFA, meaning the install will also be attributed separately.

Appsumer plans to release data focused on the specific channels benefiting from this change. “We saw people investing more in TikTok, for example,”  Lais says.

Appsumer, which provides automated reporting to performance marketing teams, released data this week analyzing the impact of Apple’s App Tracking Transparency on larger and smaller advertisers.