Apple is facing a £2bn legal action on behalf of thousands of UK app developers who allege its privacy framework hit their ad revenue while favouring its own services.

In 2021, the tech giant introduced its App Tracking Transparency (ATT) Framework, a feature that requires apps to obtain user consent through a pop-up window before tracking their activity across other apps and websites. If users opt out, the app is blocked from tracking data used to deliver targeted ads.

The claimants, represented by law firm Hausfeld, allege that the ATT framework was designed and implemented unfairly and without proper consultation. They also claim that these strict requirements don’t apply to Apple’s own offerings, with the tech firm using an internal pop-up to request user consent to personalised advertising. This requirement they claim is “less burdensome" than those imposed on third-party app developers, giving Apple an unfair competitive advantage.

Many developers rely heavily on digital advertising...