Meta has been sued for allegedly building coding into Facebook and Instagram apps for iPhones that gets around recent privacy settings introduced last year by Apple to stop user tracking.

A suit filed Wednesday in San Francisco federal court by two Facebook users is seeking class action status.

Meta’s Facebook and Instagram apps for Apple’s iOS “inject JavaScript code onto websites visited by users”, according to data privacy researcher Felix Krause.

Once installed, the code allows Meta to track “anything you do on any website.”

According to the suit, the apps skirt the iOS requirement that all third-party apps obtain permission before tracking user activities, by opening web links in an in-app browser, rather than the phone’s default browser.

“This allows Meta to intercept, monitor and record its users’ interactions and communications with third parties, providing data to Meta that it aggregates, analyses, and uses to boost its advertising revenue.”

A Meta spokesperson dismissed the allegations as being “without merit”, saying the company will defend the suit.

“We have designed our in-app browser to respect users’ privacy choices, including how data may be used for ads,” the company said.