Internet behemoth Google on Tuesday said it plans to roll out Privacy Sandbox for Android in beta to mobile devices running Android 13 starting early next year.

"The Privacy Sandbox Beta will be available for ad tech and app developers who wish to test the ads-related APIs as part of their solutions," the company said.

To that end, developers will need to complete an enrollment process in order to utilize the ads-related APIs, including Topics, FLEDGE, and Attribution Reporting.

Topics, which replaced Federated Learning of Cohorts (FLoC) earlier this year, aims to categorize user interests under different "topics" based on their device web browsing history. These inferred interests are then shared with marketers to serve targeted ads.

FLEDGE and Attribution reporting, on the other hand, enable custom audience targeting and help measure ad conversions without relying on cross-party user identifiers, respectively.

Organizations can also request access for a limited number of devices to test the Beta, plus register any apps which will utilize the Privacy Sandbox APIs.

The development comes after the search and advertising giant expanded the initiative to include its mobile operating system in February 2022, and followed it up with a developer preview in May 2022.

Privacy Sandbox is an effort led by Google to create a set of web standards for websites to access user information without compromising on privacy. It aims to facilitate online advertising without resorting to invasive methods like third-party tracking cookies or fingerprinting.

That said, the company's plans to turn off third-party cookies in the Chrome web browser have been delayed twice, with the technology now expected to be phased out sometime in the second half of 2024.

To complicate matters further, the proposals have drawn criticism from rival browser vendors like Mozilla Firefox and developers of other Chromium-based browsers such as Brave, Opera, and Vivaldi, who have said the newer methods would cement "Google's position as a web monopolist."

DuckDuckGo, which blocks Privacy Sandbox through its Chrome browser extension as of May 2022, said Topics allows Google to surveil users' online activities and share that information with advertisers for behavioral targeting without their consent.

"This targeting, regardless of how it's done, enables manipulation (ex. exploiting personal vulnerabilities), discrimination (ex. people not seeing job opportunities based on personal profiles), and filter bubbles (ex. creating echo chambers that can divide people) that many people would like to avoid," the company noted.

Despite the pushback, Google said it's looking to engage with the broader ecosystem and gather "continued feedback as we enter this next phase of testing."