Post-ATT Media Spend Index: Week 7

Post-ATT Media Spend Index: Week 7
June 17, 2021 Simon Whittick

We’ve just seen iOS 14.5+ adoption jump past the 60% tipping point according to the folks at Branch. This means that mobile app advertisers can no longer kick the can down the road on App Tracking Transparency (ATT) and SKAdNetwork (SKAN) implementation, by relying on traffic from older versions where the IDFA is still present.

Most mobile app advertisers now need to adjust to this new normal in terms of measurement and media spend. So how are they adjusting media spend? Well that’s what we’ll be looking at in the coming weeks with our “Post-ATT Media Spend Index”. Some key points to highlight on our data are:

  • We’re looking at over $500m of annualised ad spend across over 100 apps.
  • We only look at apps who have been spending consistently over the period analysed.
  • It’s a longitudinal study starting with the first week of the year up until last week, with ATT enforced in week 17.
  • The dataset isn’t representative of the whole market, it skews towards bigger spending apps based in North America and Europe.

Without further ado, let’s take a look at the numbers from last week …

More significant moves of spend towards Android

What’s become clear over the last two weeks is that advertisers are starting to shift spend from iOS to Android as iOS 14.5+ adoption increased. 

From a pre-ATT average in 2021 of a 60:40 split it moved to a 62:38 split in favour of Android. With iOS 14.5+ adoption now over 60%, this trend could become more pronounced in the coming weeks.

Smaller advertisers moved most

In terms of where that movement is coming from, it appears to be amongst small and mid-sized spenders, whilst larger spenders remain solid.

The smallest spenders have dropped their iOS share of spend seven percentage points from a pre-ATT 2021 average of 31%. Meanwhile, mid-size advertisers dropped it 11 percentage points. However, we did see a surge of iOS spend from this category before the ATT rollout, which does lift that average slightly above normal levels. Despite seeing a slight decline from large advertisers last week, they’re still only down one percentage point from their pre-ATT 2021 average.

We’d suggest that larger advertisers have more significant resources to help them better prepare from a measurement and optimisation perspective to ride out the change. They also have a more diversified media mix, which helps in volatile times.

All major cross-OS media channels saw a movement

Whilst Apple Search Ads are only on iOS, all other major Self Attributing Networks (SANs) have started to see a swing of spend away from iOS.

The most significant swing was for Snap, which is now down 14 percentage points on its pre-ATT 2021 average of 63% of spend on iOS. TikTok was down eight percentage points from 50%, however, their spend is still more volatile given most advertisers are still experimenting with the ad channel. The duopoly of Facebook and Google are both down seven percentage points from their pre-ATT 2021 averages of iOS share of spend.

No winners or losers amongst media channels, yet

Whilst advertisers are moving spend from iOS to Android, it appears that the spend is largely staying in the same channel for now when looking at share of wallet across iOS and Android.

Whilst Facebook looked like it was starting to decline 2-3 weeks ago, that trend didn’t stick last week and they’re currently only one percentage point down on their pre-ATT share of wallet average. However, advertisers are reporting CPMs shooting up on Facebook iOS traffic as iOS 14.5+ adoption increases. Their popular Value Optimisation (VO) and App Event Optimisation (AEO) targeting types will lose useful signals as the IDFA increasingly disappears. This CPM increase could be the cause of share of wallet increases and the resulting performance losses could mean advertisers reduce Facebook investment in the coming weeks.

Like Facebook, other major channels have only seen marginal movements in share of wallet since ATT was enforced. Google is down two percentage points, whilst Snapchat and TikTok are both as they were before. Apple Search Ads are unsurprisingly up one percentage point, but nothing like what might have been expected pre-ATT. Other long-tail ad networks are also up one percentage point.

In general, the real winners and losers of iOS 14.5+ from a channel perspective won’t reveal themselves for a few weeks. With iOS 14.5+ only just reaching mass adoption, the IDFA has had a stay of execution. However, that’s unlikely to be the case as we look at this data in the coming weeks.


Advertisers are clearly reacting to iOS 14.5+ adoption increasing as they switch spend from iOS to Android. However, the impact of disappearing IDFAs on individual channel performance hasn’t been revealed yet. Expect that to reveal itself in the next few weeks of data. Sign-up to our newsletter to get notified whenever we share new data.

Also, if you’re still trying to work out how to optimise campaigns using limited signals from SKAdNetwork (SKAN), you should join our webinar on July 7th “Under the hood of SKAdNetwork (SKAN): Getting maximum value from limited signals”. We’ll be joined by some of the brightest minds on SKAN to share early lessons and tips from working with Apple’s attribution tool. Fill out the form below to reserve your place for the live session and get your questions answered.