What does iOS 14.5 and ATT mean for my Facebook Campaigns?

How will iOS 14.5 and ATT restrict the data Facebook will receive?

What will it mean for Facebook Audience targeting

What is the impact on Google Analytics

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by Al Taylor
Updated June 28th 2021

Section 1:

Apple iOS 14.5 - what's happening

New pop-up will ask Users if they will allow an App to track them

Only one piece of anonymised event information will be passed back to Facebook or advertiser

The launch of iOS 14.5 in spring 2021 is another step towards giving users greater control over their data privacy.

Apple is requiring all Apps on its App Store to agree to a new App Tracking Transparency (ATT) framework (if the App collects data about the end user).

Starting with the operating system iOS 14.5, users will be asked, via a pop-up, whether to allow an App to track the user’s activity across its and other companies’ Apps and websites.

If the user ‘Asks App not to Track’ then Apple will not disclose the IDFA (IDentifier For Advertisers) which is a unique device identifier.

Iphone with pop-up asking if user would like to ask the App not to track

Apple will use a new feature called Private Click Management (PCM) for measuring ad clicks across websites and from iOS Apps to websites. Learn more on the webkit site.

PCM allows only one piece of event data (a piece of event data could be a purchase, page view, download etc) to be transferred to the ad provider (say Facebook Ads or Google Ads) and this one piece of data is sent randomly between 24 and 48 hours after the event (not the click on the ad).

This delay protects the user’s identity as it becomes much harder to link the click with the event.

Users on the Safari browser also have the option to opt-out of PCM.

Section 2:

How Facebook Ads is Responding to ATT and iOS 14.5

Facebook uses a framework called AEM (very similar to ATT).

Facebook now limits you to only 8 triggered events and you have to prioritise them.

For Apple iOS14.5 users that have asked the ‘App not to Track’ you get one piece of event data for the highest prioritised event that was triggered.

Our understanding of the impact is this:

Facebook will use a system called Aggregated Event Management (AEM) that abides by the principles of Apple’s PCM (Private Click Management).

Prior to the implementation of ATT, Facebook allowed an almost unlimited number of events to be tracked on a website (such a product page view, add to cart, download, etc).

Each and every time an event was triggered by a user on a website then the facebook pixel posts the event information to Facebook.

Limited to 8 events you collect data on

With the introduction of Apple’s ATT framework, Facebook is now limiting accounts to only 8 events per domain.

(What is one domain? Well, www.example.com/us and www.example.com/uk are treated as the same domain while www.example.com and www.example.co.uk are treated as separate domains).

Facebook will automatically select the 8 events you are now limited to. But you can then edit the selection in Events Manager. [If the account is new then you can create the 8 events].

Prioritise events – you only get one piece of event data per visit

You also need to prioritise these events from most important to least important.

The new process will only send one piece of event data per click from iOS14 devices that have asked Facebook not to track the App’.

By setting the prioritization you can decide which piece of information to send.

Typically you want to know about the most valuable event on your site such as a conversion for an e-commerce shop.

If the click doesn’t result in a conversion then the next most important event data (as prioritized by you) is sent (which may be product view or Add to cart).

This one event data causes a problem if you run your campaigns using Value Optimization (i.e. you are trying to optimize the value of conversions rather than just the number of conversions) as you need to know two pieces of information: was there a conversion and how much was it for?

Facebook has come up with a fix. They have moved Value Optimization to be managed in Events Manager. You will need to enable ‘Value Set’ in Events Manager.

If you enable Value Set then rather than having one event for conversion, Facebook automatically creates four conversion bands (value sets).

The four value sets might be: conversion with value between $0-$50; conversion with value $50-$100; conversion with value between $100-$200 and conversion with value >$200.

Now if someone converts then the single piece of data can be, for example ‘one conversion with value between $100 and $200’.

You don’t have to stick with just four bands – you can use all 8 of your events for value sets. This allows for more granular value buckets but means you will collect less data about events done by users who did not convert.

If you select a new event or change the prioritization then it will take three days before you can start optimizing to that event (as it may take 3 days to get initial data back: 24-hours for the event to be triggered after the click + up to 48 hours to be notified of the event after the event happened).

What to do now

Verify Domain – you must verify that you are the domain owner. Learn more on Facebook.

Decide on top 8 events – Facebook will make the initial decision but then you can edit.

Section 3:

Impact on Facebook Measurement

Facebook changing conversion windows

1-day View through and 7-day click through to only include conversions Facebook sees. 

Facebook is deprecating its 28-day click-through; 28-day view through and 7-day view-through windows.

The delivery attribution window (this is the attribution window you want to optimise performance by) will continue to be set at the Ad Set Level (e.g. optimize conversions based on 7-day click).

Previously, regardless of the delivery attribution window you had chosen to optimise the ad-set on, you could use the reporting tool to view, at an account level, the performance of the campaigns through different attribution windows.

Now on the reporting tool you will only be able to see performance through the same attribution window you have targeted.

Is the reporting data as accurate as it was?

The 1-day Click data will be modeled – a combination of actual conversions and estimate for conversions via iOS14.5 devices.

Facebook models the iOS 14.5 conversions not because it won’t ultimately know this number accurately (if you have set conversions as your top event priority) but because it takes up to 3 days to get the actual conversion date from Apple and the one piece of data received via AEM will be at the campaign level so an estimate for the split by Ad Set is also needed.

The 1-day view and 7-day click windows will be partial conversions (only people not on iOS14.5 or iOS 14.5 users that have asked to allow the App to Track).

Note – there still will be conversions on devices where people have opted out of tracking but Facebook will not be told of them and has decided not to model these.

Diagram showing how Facebook Changes to how Results are measured from iOS 14.5

Section 4:

ATT Impact on Facebook Targetting / Audiences

Facebook targetting will be less accurate as it will not be able to identify individuals (that have asked not to be tracked) who have converted or say viewed a product

Facebook can see who has clicked on your ads but for people that have asked not to be tracked it doesn’t know if that individual made a conversion (if conversion is your top prioritized event it will know in aggregate how many conversions have been completed but not which individual users actually made the conversions).

This means Facebook might include purchasers in audiences where you have asked to exclude them (such as exclude purchasers in remarketing campaigns or in prospecting campaigns).

It will also mean that it won’t be able to include people who have opted out of tracking in remarketing audiences based on events such as viewed a product.

Impact on Lookalike audiences

The accuracy of a ‘Lookalike Purchasers’ audience will diminish. 

Surely Lookalike Purchasers will only work if Facebook knows who purchased?

Well Facebook will know who has clicked on the ads, plus the identities of people who have not opted out of tracking and purchased. For people who have opted out of tracking it will know who clicked but not which specific individuals have purchased (it will know the campaign) – so it still have quite a lot of data to create a profile of a purchaser.

Section 5:

ATT Impact on Web Analytics, Google Analytics and UTM Parameters

We think there won’t be any impact.

With UTM Parameters and Google Analytics you should see events not tracked by Facebook.

We don’t think there will be any impact on your Google Analytics reporting.

UTM Parameters will still work and if you have set up your Campaigns and Ad Sets to include UTM Parameters then you can can see via Google Analytics the number of last non-direct conversions by Campaign and Ad Set.

In fact, even for people that have asked to not be tracked and do not have their unique device identifier (IDFA) shared with Facebook, the fclid tracking data would allow Facebook to collect lots of data about the purchase.

It appears that Facebook recognises that this would be against the spirit of the request to not track and will not collect this information going forward if the user has requested not to be tracked.

It means that via Google Analytics or alternative web analytics tool you may see events of people that have asked not to be tracked (if you have UTM Parameters set up) while Facebook will not report on these events.