Q&A with Remerge: Collaborative testing ahead of the Google Privacy Sandbox rollout

Privacy Sandbox on Android will not affect the programmatic advertising industry until the end of 2024, at the earliest. However, after Apple’s App Tracking Transparency (ATT) mic drop in 2021 and its impact on iOS campaign measurement since then, can you blame mobile marketers for feeling a little nervous about what Google is planning with its privacy-centric framework?

Google’s privacy initiative includes a set of APIs that will facilitate the on-device buying, selling, and targeting of in-app ads without sharing user data among third parties. The rollout of the solution is a landmark for protecting personal information on mobile but it also requires an industry-wide collaboration, with ad tech players now reworking their tech stacks and familiarizing themselves with a completely new infrastructure.

To prepare marketers for the Privacy Sandbox launch, Adjust is working closely with partners at the forefront of the transition, like Remerge, a retargeting-focused demand-side platform (DSP). Earlier this year, we collaborated to conduct testing of Google’s Protected Audience API, which involved using Adjust’s SDK to build custom audiences for re-engagement campaigns.

In this article, Luckey Harpley, Staff Product Manager at Remerge, answers questions on Privacy Sandbox on Android, discussing how re-engagement will work and the importance of Remerge and Adjust’s Custom Audience Delegation test.

Users want more autonomy over how tech companies manage their personal information. The advertising industry is swiftly moving towards a privacy-centric future and marketers have no option but to adapt to this environment, whether it’s now, if they want to be fully prepared, or later, when they’ll be playing catch-up.

On mobile, ATT was the first big initiative that really shook things up. Back in 2021, Apple changed the game when they introduced its framework that requires iOS users to opt-in to in-app tracking via a mandatory prompt when sharing their device IDs with advertisers.

Google’s response is Privacy Sandbox on Android, which will provide tracking and reporting via its Attribution API, targeting through Topics and Protected Audiences APIs, and data collection and handling via the SDK Run Time.

Unlike with the ATT rollout, Remerge is working directly with Google and our partners to test and build solutions that work for future mobile ad campaigns on Android. This is no easy feat, however. The transition to this framework requires a significant change in how our technical infrastructure works, from algorithm and database changes, to in-app event collection and third-party integrations. At Remerge, we have a dedicated in-house team for the Sandbox initiative, which has been working on this project for over a year.

Right now, our priority ahead of the Privacy Sandbox on Android rollout is to ensure everything is ready for our customers to run re-engagement campaigns on Android without experiencing a significant drop in performance.

Google’s Protected Audience API will allow us to target our clients’ users in a privacy-preserving way, because it doesn’t rely on cross-app IDs. Instead, users will be added to what Google is calling a “custom audience”. These are groups of users that correspond with interests and desired in-app actions determined by the advertiser. Android will store information about these groups on the user’s device and will not reveal which custom audience a user is a member of.

We’ll work with our clients to define specific in-app behaviors for a retargeting campaign, such as adding an item to a shopping cart or making a first purchase. When a user completes a desired action like this, they’ll land in a custom audience and we’ll use this information to bid on and show them a relevant ad.

Our MMP partners, like Adjust, are pivotal to our progress here. We’re working together to better manage and optimize programmatic ad buying and segmentation targeting on Android, so it’s a smooth process for advertisers when the rollout comes into effect.

Part of the Protected Audience API includes the Custom Audience Delegation, which lets us create and add users to custom audiences on the device utilizing our MMP partner SDKs.

We recently completed our first successful test for this process with the team at Adjust. Using a Protected Audience API plugin, the Adjust team opened an emulated test app with a test MMP SDK. Upon opening the app, the test SDK called fetchAndJoinCustomAudience(), which then called the Remerge fetch URL.

Essentially, this process was asking us to check if this user belongs to any of our advertisers' campaigns, and allows us to respond with any Custom Audience definitions that we want the user to be joined to for the purpose of future bidding. We replied with “yes, please add the user to this custom audience”, and the user successfully joined. While it may sound like a small win, it’s actually a very important early step in our Sandbox testing – it demonstrates that the Protected Audience API and custom audiences mechanisms are working as planned and validates both Remerge and Adjust’s product capabilities.

Getting the right technical setup is challenging and compared to ATT, we’re finding that Privacy Sandbox on Android is a bit more complicated. The good news for advertisers is that ad tech players are pulling together to make sure the move to Google’s new framework is a success. Advertisers won’t experience a significant change in the buying process from their side and the tools they’re using will likely be very similar to what they have now. In the end, they’ll be able to run scalable engagement campaigns without compromising user privacy.

We're not just improving our product. We’re also helping shape the future of privacy-first programmatic advertising with our partners.

We’ll continue to work closely with MMPs, such as Adjust, and Google, to build the best solutions for measurement and attribution. We’re also working with supply partners to run automated ad buying auctions based on the Privacy Sandbox framework. On top of this, we’ll carry on sharing our Sandbox learnings with the industry and exchanging knowledge with ad tech players to further improve our testing processes.

My advice for advertisers at the moment is to research Privacy Sandbox on Android and stay on top of the latest developments. They can also reach out to their partners. The Remerge team, for instance, is more than happy to chat about what is happening in this space and how developments are likely to impact marketers in the long run.

Learn more about Remerge or read Adjust CPO Katie Madding’s take on what’s to come as we prepare for the rollout of Google’s Privacy Sandbox.