iOS 14 vs Facebook - How will it impact advertisers and brands?

December 21, 2020

Amongst all the flashy new tools and features of Apple’s iOS 14, the addition of one little box has the potential to cause significant headaches for advertisers, and has even prompted Facebook to take out newspaper ads attacking Apple.

Apple vs. the free internet article

What’s happening?

In the latest iOS14 update, Apple is requiring all apps to provide a prompt when a user opens an app for the first time. They’ve called this Apple AppTrackingTransparency (ATT). This prompt will allow the user to decide if they’re happy to be tracked by the app or not. 

In Apple’s words, “Tracking refers to the act of linking user or device data collected from your app with user or device data collected from other companies’ apps, websites, or offline properties for targeted advertising or advertising measurement purposes.”

Screenshot - Tracking permission

Why has this annoyed Facebook?

Whilst many people will likely click the ‘Allow Tracking’ option, from Facebook’s perspective, having to show this prompt is potentially extremely damaging to their business.

If a user selects ‘Ask App Not to Track’, then Apple will do just that and the user data won’t be shared. For Facebook, having to explicitly ask people a question containing the phrase ‘Facebook would like permission to track you across apps and websites’ , is likely to result in a large number of people clicking No.

Without consent to undertake this tracking, Facebook won’t be able to serve personalised ads, track conversions, or power their advertising tools which are dependent on rich user data.

This will make it harder for advertisers to deliver successful campaigns across the Facebook Ads platform, and importantly make it much more challenging to track results.

What it means

The impact of this change is significant, and Facebook are already planning widespread conversion tracking changes to try and address this. You can read about these changes in full detail here, but we’ve provided a summary of the major changes below.

Event Management

Aggregated Event Measurement

There isn’t a huge amount of detail provided on this, but Facebook will be introducing Aggregated Event Measurement, which essentially means they’ll use a modelling process to try and measure results and campaign performance.

Event Limits

You’ll be limited to the use of 8 conversion events per domain. Beginning early 2021, advertisers will have to select which of their events to prioritise and report on.

Value Optimisation

If you’re a large scale advertiser who uses Value Optimisation, there’s a number of changes in terms of how this appears within the Facebook Ads dashboard. Value sets for these will count as part of the 8 events you’re allowed to track for your domain. 

Dynamic Ads

Audience sizes for dynamic ads are expected to drop for retargeting, however performance should remain fairly unchanged as you’ll still only be showing ads to a trackable audience.


Attribution Windows

28 day windows will no longer be supported, nor will 7 day post view. Statistical modelling will also be used for certain attribution windows to make up for the reduction in data from iOS 14 users. An annotation will be shown in the platform when modelling is used.

Attribution Window selection will be entirely at the ad set level, removing account-level options.

Offline Actions

These will now be reported on based on when the conversion happened, rather than when the initial ad impression took place.


For developers, there will be a number of changes to the Marketing, Ads Insights and Targeting API, so we suggest working through these as soon as you can and reviewing the latest changelog.

What Facebook are recommending you do now

  1. Verify your domain in Facebook Business Manager. Here’s the support article for how to do this

  1. Plan for only having 8 events to optimise to. We encourage you to make sure these are the ones which are business critical and provide the most value to you.

  1. For Dynamic Ads, verify product URL domains in the catalog feed and prepare to use only 1 pixel per catalog to optimize.

  1. Use the Comparing Windows attribution feature to see how the change from a 28 day window to a 7 day window will impact you.

What about lead generation ads?

For lead gen advertisers, the good news is that lead generation ads are largely unaffected by these updates.

Robust first party data is as valuable as ever, and with personalised advertising across Facebook and Instagram becoming more challenging with these changes, it’s important to think about how you can use Lead Generation ads to collect data and fuel your other communication efforts.

You can read more about Facebook Lead Ads here.