Android phones generate unique advertising codes, similar to Apple's Identifier for Advertisers (IDFA), that allow Google and third parties to track users' browsing behaviour in order to better target them with advertising.

Schrems' campaign group Noyb argued that in creating and storing these codes without first obtaining explicit permission from users, Google was engaging in "illegal operations" that violate EU privacy laws.

Noyb urged France's data privacy regulator to launch a probe into Google's tracking practices and to force the company to comply with privacy rules. It argued that fines should be imposed on the tech giant if the watchdog finds evidence of wrongdoing.

Stefano Rossetti, privacy lawyer at Noyb, said: "Through these hidden identifiers on your phone, Google and third parties can track users without their consent. It is like having powder on your hands and feet, leaving a trace of everything you do on your phone -- from whether you swiped right or left to the song you downloaded."

Last year, Schrems won a landmark case at Europe's highest court that ruled a transatlantic agreement on transferring data between the bloc and the US used by thousands of corporations did not protect EU citizens' privacy.