The anticipation of the rollout plan on Google’s Privacy Sandbox is high among marketers, especially after Google’s announcement to phase out third-party cookies in Chrome by the second half of 2024. This move has captured the attention of app developers and ad tech companies, raising questions about the potential deprecation of Google Advertising Identifier (GAID) on Android. Performance marketers are adapting to the rapid pace of change as ongoing privacy restrictions continuously reshape the advertising landscape — and they have to brace for another significant shift in how they plan and implement marketing campaigns within the future Privacy Sandbox framework.
Where we stand today
Given Android’s complex OEM ecosystem, the GAID deprecation is expected to unfold more slowly than iOS’s App Tracking Transparency (ATT) changes, with no significant impact on Android marketing expected before the end of 2024. But, we also expect Google is likely to announce GAID changes before covering all Android devices, mirroring ATT’s phased introduction with iOS 14.5 and above.
Globally, Android holds a 42% larger market share than iOS, making the implications from Google’s Privacy Sandbox for mobile marketing substantial. Even imagining a GAID restriction limited to just Android versions 13 and 14 would impact about 23% of the entire Android marketing industry, underscoring the urgency for mobile marketers to align with ad tech companies on the Privacy Sandbox integrations.
Keeping up: iOS vs. Android privacy frameworks
Although the mission of prioritizing user privacy remains the same, ad tech giants Google and Apple have different nuances to their privacy-centric attribution frameworks.
| Initiative goals | iOS Strategies via ATT & ITP |
Android Strategies via Privacy Sandbox |
| Reduce user-level tracking by restricting user identifiers. | Apple implemented ATT as an opt-out default starting with iOS 14.5 and restricted IDFA usage for targeted device marketing. Additionally, ITP blocks third-party cookies on Safari by default. | Google intends to restrict tracking via third-party cookies and GAID for web and Android, enhancing privacy controls. |
| Reduce cross-site and cross-app tracking. | ITP partitions website data storage and activates fingerprinting defense by default to prevent cross-site tracking. | In addition to phasing out third-party cookies and GAID, the Privacy Sandbox will also restrict fingerprinting and IP address tracking on the web to reduce cross-site tracking. |
| Prevent third parties from inheriting the host app’s privileges, permissions, and access | N/A. Apple has implemented Privacy Manifest, requiring app developers to record the categories of data that their third-party SDKs collect and the reasons for collection. | Privacy Sandbox includes a planned SDK Runtime, which prevents third-party SDKs from inheriting the host app’s permissions and accessing its memory, enhancing security and privacy. |
| Support privacy-preserving alternatives for key advertising use cases | SKAN | Android seeks to provide both ads measurement and relevant capabilities with new APIs proposed under the Privacy Sandbox |
Addressing today’s business needs under the Privacy Sandbox
In light of the evolving privacy frameworks within both the iOS and Android ecosystems, it’s evident that user-level tracking will become increasingly restricted, including ID limitations and reduced cross-app and cross-site tracking. Additionally, third-party SDKs’ permissions and data access will be further constrained.
In the face of the evolving changes surrounding privacy-centric attribution, businesses have expressed interest — or really concern — in sustaining their marketing capabilities in key areas. Google’s Privacy Sandbox introduces several innovative solutions to address these business needs while prioritizing user privacy.
Build and manage target audiences
| Protected Audience API | Topics API | Protected App Signals API | |
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| Reengagement | |
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| Retention and activation | |
Marketers today have relied heavily on user-level identifiers to effectively build and target key audiences for reengagement, retention, and activation campaigns. While this has been a great way to accurately reach target audiences, the focus on user-level privacy changes the way marketers will have to think about audience building and management, which Google aims to address with:
- Protected Audience API – for retargeting. To effectively engage with users, marketers often need to build campaigns based on how users have previously engaged with their app. This is commonly thought of in re engagement, retention, and activation campaigns. An example might be a pet store app that wants to advertise to users who have left an item in their cart in the past 24 hours to remind them to complete the purchase. This API enables the grouping of users based on criteria specified by the app, facilitating targeted advertising while maintaining user privacy.
- Topics API – for personalization. In mobile advertising, advertisers aim to present ads that align closely with a user’s interests. For instance, to create a more engaging and personalized experience, someone who frequently engages with running apps would likely find ads about running topics more appealing than unrelated ads. The Topics API plays a crucial role here by generating broad interest signals, known as topics, directly from a user’s app interactions. These topics are determined on-device, ensuring privacy, and are then provided to advertisers. This allows marketers to build more relevant advertising based on a user’s demonstrated interests without the need to track individual user activity across different apps.
While the examples above illustrate the primary use cases we expect, advertisers and DSPs can ultimately select the APIs that best suit their specific needs.
Understand how your marketing is performing
Historically, most marketers have understood their attribution and measured campaign performance by leveraging Advertising IDs, such as GAID. However, in a world where marketers cannot rely on user-level identifiers like GAID, they will need an alternative way to continue measuring attribution and curating accurate reports on their marketing performance. Google’s Privacy Sandbox aims to address this need with:
- Attribution Reporting API – for measurement. The Attribution Reporting API enables privacy-focused measurement of digital ad performance across apps and the web by removing the reliance on cross-party user identifiers. This will ensure cross-app-and-web attribution while prioritizing user privacy. Marketers at a gaming company, for example, may want to measure which country had the best performance with their newly released game, which they could understand at an aggregate and event level with this reporting API.
- SDK Runtime – to isolate SDK execution. To add more value, the SDK Runtime provides a secure environment for executing third-party SDKs, such as a unified “SDK Store.” This isolates third-party SDKs from direct access to user data and app resources and enhances privacy and security by controlling the SDK’s interaction with the host app and user information.
While several other APIs in the Privacy Sandbox framework can be explored, we believe the ones discussed here represent the core components essential for understanding the shift toward more privacy-conscious advertising. These APIs lay the foundation for a new era in digital marketing, where user privacy, effective targeting, and performance measurement coexist.
How Branch is navigating a post-identifier deprecation landscape
Google’s Privacy Sandbox evolution signals a continued shift toward a more privacy-focused digital marketing ecosystem, urging ad techs and apps to embrace new marketing technologies and strategies.
At Branch, our ongoing focus is on offering privacy-compliant attribution and measurement. We are actively collaborating with Google’s Privacy Sandbox team, participating in live tests, and contributing feedback to the designed initiatives. Our goal is to enhance the privacy-focused mobile advertising ecosystem together while continuing to support thriving digital businesses.
As the industry shifts toward an ID-restricted landscape with increased noise added to reporting, Branch is also developing a new holistic-based reporting system. This system will strategically manage noise and offer customization options — along with our expert recommendations on measurement goals, tracking granularities, and aggregation periods — to ensure that Branch continues to deliver actionable insights. Beyond probabilistic approaches, Branch is also advancing toward using multi-data and sophisticated modeling to provide deeper insights into ad spend allocations and more.
While we navigate changes like the deprecation of third-party cookies, Branch also ensures that our deep linking and Journeys offerings remain unaffected. We are supporting your marketing efforts as before.
We will continue to share practical insights and updates on our navigation of the Privacy Sandbox. We are moving into live testing and welcome interested apps to join us in this initiative. If you’re ready to take that step, we invite you to contact us! For more on Privacy Sandbox, check out our recent TechTalks webinar, “The Unpopular Truth About the State of Privacy.”