Another year, another WWDC and another iOS update. This year’s Worldwide Developers Conference introduced iOS15, a host of new privacy features and highlighted Apple’s ongoing commitment to consumer data privacy. The takeaway? Players with a history of user acquisition and proprietary first-party data will be well-equipped to engage users in a post-iOS14 world. We cover the highlights of WWDC 2021 and why programmatic UA is more important than ever in light of Apple’s latest announcements.

WWDC 2021 Privacy Highlights

With Apple’s iOS15 updates, Apple is building on the data privacy measures they first launched with AppTrackingTransparency on iOS14. The next version of iOS will give Apple's customers additional ways to limit data-sharing. These privacy features include tools to mask email and internet addresses. This will make them less effective as a unique identifiers for tracking.

YouAppi CEO and Founder, Moshe Vaknin, said of the new privacy enhancements, “This will make opt-ins and first-party data even more valuable, fanning the flames of innovation needed for marketers to effectively target, track and engage end users.”

Hide My Email Feature

At WWDC, Apple unveiled its Hide My Email feature. This is an upgraded version of existing functionality that enables users to create a randomized email address when they register with an app. This, in turn, prevents advertisers from tracking the same consumer across different platforms while still allowing one-to-one communication with customers who opt into their email communications.

What This Means For Marketers

Marketers will have to double down on personalizing emails and SMS messages sent from their websites to reach people. What does doubling down look like exactly? Leveraging emailed promotions and offers with compelling subject lines; enticing people to share information about their purchase intent and preferences via short surveys that offer discounts. By collecting this information directly and consensually, marketers have an opportunity to build a one-to-one connection with their customers that also honors their privacy.

Private Relay Feature Hides IP Addresses

With iOS15, Apple unveiled Private Relay. This new feature that encrypts web browsing data and assigns an anonymous internet protocol (IP) address to a user. This will make it more difficult for sites to track users’ browsing activities across both websites and apps.

What This Means For Marketers

Marketers will need to refocus on creating valuable, human interactions with their customers. No longer can they depend solely on data to engage them. This includes building compelling creatives that reach a broader and more diverse audience. It also means marketers will need to ask users directly about their preferences and information in relatable and captivating ways.

Programmatic User Acquisition on iOS14.5+

A Note on Probabilistic Attribution and Contextual Targeting 

In a post-IDFA iOS reality in which data privacy features continue to evolve, never has it been more important for marketers to undertake programmatic user acquisition with experienced players with an existing inventory of first-party data. As we’ve written about before, mobile marketers will still be able to leverage probabilistic attribution and contextual targeting signals despite Apple’s changes in the following ways:

  • Probabilistic Attribution: Through probabilistic attribution, advertisers can assign campaign membership probabilities to a user based on attributes, behaviors, and anonymous user-level in-app data.  SKAd postbacks containing campaign ID, source app ID and conversion value can also supplement this data; also, ad network-reported data showing installs, impressions and spend.
  • Contextual Signals: Contextual signals indicate to marketers what kind of ad creative to deliver within the context of the app. This is based on anonymized user behavior data (mentioned above) and device-based contextual signals. These signals include the strength of network connection or battery level. A dying battery, low storage space or poor network connection are all indicators that a user is unlikely to download a data-heavy mobile app; so, an ad for such an app would be less likely to perform.

Additionally, ATT opt-in rates are much higher than initially anticipated. According to AppsFlyer, 48% of actual consumer interactions with the ATT prompt resulted in an opt-in for the average app. Overall, the opt-in rate stands at 42% globally.

YouAppi’s Solution to Programmatic UA on iOS14.5+

To meet these opportunities, we unveiled our proprietary contextual targeting algorithm in March to address the oncoming challenges of Apple's IDFA changes while still enabling advertisers to meet their KPIs on iOS. Our contextual targeting solution uses a blend of probabilistic correlations and privacy-safe data to undertake an alternative type of targeting without the IDFA. Building on our existing ReAppi platform, which uses automation and machine learning to retarget high quality users, our contextual targeting algorithm harnesses interoperability while enabling probabilistic correlations.

These probabilistic tools include User Agent IDs and local IDs (publisher ID and SSP ID) that can be accessed programmatically. We also utilize contextual data such as the publisher app, device detail and limited ad session behavior of the user. This information is then combined to programmatically reach and convert high-quality users within specific user segments.

This unique blend of machine learning, scalability, quality, flexibility, and privacy-safe data has seen consistent success. As noted by Eyal Hilzerant, Chief Product Officer at YouAppi; "We have internally tested 2.5 million devices using our own contextual data parameters with an 80% accuracy when compared with deterministic (IDFA based) user acquisition campaigns"


WWDC 2021 saw the announcement of additional iOS privacy features indicating a continued trend towards a privacy-driven landscape.

  • iOS will give Apple's customers additional ways to limit data-sharing. This includes technology to mask email and internet addresses, making them less effective as a unique identifier for online tracking.
  • Marketers will have to leverage offers, promotions and compelling creatives to create valuable connections with their customers.
  • Our proprietary contextual targeting algorithm builds on the retargeting capabilities of our ReAppi platform. We utilize a blend of probabilistic correlations and privacy-safe data to undertake an alternative type of targeting without the IDFA.
  • This unique blend of machine learning, scalability, quality, flexibility, and privacy-safe data has seen consistent success. Our test campaigns have 80% accuracy when compared with deterministic, IDFA-based, UA campaigns.