The IDFA, Apple’s ATT, SKAdNetwork Timer, and what you need to know about it

Michael Stysin avatar
Michael Stysin

Apple announced its’ App Tracking Transparency (ATT) framework in June 2020, and the ATT is expected to be enforced by Apple within several weeks. Apple has postponed the policy’s enforcement several times already, but this time the deadline is getting very close. 

Who is affected the most by the ATT in the first place? 

The policy is focused on user privacy and IDFA (the identifier for advertisers) usage. If you already know what the IDFA is and how it’s used in mobile advertising, you can skip to the next paragraph. I’ll provide a quick explanation here for those who are relatively new to mobile marketing attribution.

The IDFA is a unique random iPhone ID that is assigned to the device. 

It is available for iOS developers with the advertisingIdentifier method of ASIdentifierManager

Social networks that provide advertisements, like Facebook, use the IDFA to match app users who saw an app advertisement on their network and installed that app.

For example, let’s assume you are running Instagram ads for your mobile app. A user clicks on the ad and is forwarded to the App Store to install the app. Facebook advertising engine saves this user’s IDFA, so it knows that this specific user clicked on the ad. After the user installs the app, Facebook’s advertising SDK installed in that app reads the device’s IDFA and reports it back to Facebook. Facebook matches the user to the one who clicked on the ad.  

That is how Facebook Advertising provides very accurate and in-depth data on the number of installs, in-app purchases, and lots of other valuable information on an advertising campaign level. Other platforms that provide mobile app advertising services are using the same technique. Think of Twitter, Snapchat, TikTok, and many more. And these platforms are the leading source of paid acquisition for mobile apps. If you have a high-quality app, you can grow it profitably by acquiring users from these huge networks and measuring your advertising efficiency with remarkable precision. But this is about to change. 

Apple’s ATT requires apps to ask for user consent to tracking. If a user opts out, the IDFA is not available. And once the IDFA is not available, it’s very hard to match the user and the ad that the user clicked to install the app.

The enforcement of the ATT by Apple is likely to affect app marketers in a significant way. There are estimates that more than 70% of users will not allow tracking, so the existing advertising measurement might collapse as soon as the ATT is enforced. 

There are many mobile measurement platforms (MMPs) like AppsFlyer, Adjust, Tenjin, that provide convenient mobile advertising measurement for app marketers. All of them are leveraging the IDFA to some extent, and now their marketing attribution models will also have to change. 

Here you can find Apple’s ATT overview, including the answers to some frequently asked questions.

SKAdNetwork instead of the IDFA for marketing attribution

Apple offered a solution to measure app ads. This solution does not violate user privacy and does not require the IDFA. The solution is Apple’s SKAdNetwork framework

SKAdNetwork transmits app attribution data to the advertising network on the advertising campaign level. Let’s have a look at the following simplified example:

You are running some ads for your app on Instagram. Instagram is registered with SKAdNetwork as an advertising platform. When a user clicks on the ad, Instagram sends this data to SKAdNetwork. Once a user launches the app, Apple’s SKAdNetwork registers that the user installed the app. Apple’s SKAdNetwork makes a postback to Instagram that the advertising campaign resulted in an install. There is no data on specific user shared, just the fact that a particular advertising campaign led to an install.

What are the limitations of SKAdNetwork compared to matching users based on the IDFA? 

The information that is available through SKAdNetwork is minimal. And there are many limitations on how the data is reported. 

The most important limitations are: 

  • the minimum delay SKAdNetwork reports the data to ad networks is 24-48 hours
  • only one conversion value is reported
  • 100 different campaigns limit per network

SKAdNetwork Reporting time

The install is reported within 24-hours via SKAdNetwork. 

The additional conversion value besides the install itself can be reported. But setting this conversion value delays the postback of the data. 

To include the conversion value in the postback, a developer needs to trigger the updateConversionValue method. When this method is called, the additional 24-hour timer is started. The developer can reset the timer by invoking the method again and provide the new conversion value. If there is no further update, the value is reported in 24 hours. When this timer expires, SKAdNetwork randomly returns the attribution data to an ad network within the next 24-hours. So the lag between app install and the data received by an ad network can be 72 hours and more.

Possible reporting time:

Install -> Conversion value update within 24 hours -> postback at the expiration of 24 hours -> data reported to an ad network within the next 24 hours. 

In any case, the minimum delay is 24-48 hours if you update the conversion value just once. This makes it virtually impossible to adjust marketing in real-time. 

SKAdNetwork Conversion value

The conversion value has a 6-bit limitation. There are a maximum of 64 unique conversion values. And the consecutive conversion value update needs to be higher to be recorded. For example, “onboarding passed event” that reads 000001, then the user performs a “start a free trial event” with the value of 000011.

SKAdNetwork Campaigns Limit

The next important limitation is the number of campaigns per network. The current limit is 100 campaigns. Facebook allows just 9 active campaigns with 5 ad sets according to its iOS 14 guidance

What else to keep in mind when transitioning to using SKAdNetwork for marketing measurement? 

It’s important to note that you can still access the IDFA if a user provides his consent within the ATT framework. So it is a good idea to provide some explanation to your users why it is beneficial to them to allow tracking. 

The information on the ATT and SKAdNetwork is being updated frequently. We may update this article as more information is available.

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