The Meta Platforms share price continued its slide yesterday with a 2% loss taking the drop in valuation for the year to over 36%. The latest blow to Facebook’s new holding company comes as Google announced it is to take the lead set by Apple and stop users of Android, its market-leading mobile operating system, from being tracked across apps.

Google yesterday announced it wishes to “use the bar for user privacy” by blocking the cookies marketers use to collect data and then follow people with ads across apps and platforms.

Apple taking the same step last year was considered a major blow to Facebook’s ability to maintain ad revenue growth and one whose impact will start to become clear this year. It is estimated it will cost the company $10 billion in lost revenues. iPhone and iPad devices have a share of the mobile operating system market of just under 30% last year.  Apple users are important to marketers because they have higher average income and consumer spending.

However, Android users represent almost 70% of the mobile device market. The Android operating system following Apple’s lead to restricting cookies significantly changes the mobile digital marketing landscape. And is bad news for a social media platform like Meta that generates the bulk of its income from ad revenues.

The change will involve Google phasing out advertising IDs, which are unique codes assigned to Android devices allowing marketers to track details about their activity. More user data-friendly alternatives are being looked at.

Google has, however, said that it will take at least two years for it to roll out all changes and it will take a collaborative approach that will include dialogue with marketers. That stands in some contrast to Apple’s more direct approach last year.

However, the move would still be expected to have a major impact on advertisers and companies that generate most of their money from advertising, such as social media apps. Even Google itself could take a hit on advertising revenues as the new approach to privacy would presumably affect retargeting services and products like Google Adsense.

Advertisers like Meta, which owns Instagram and WhatsApp as well as Facebook, argue that tracking user behaviour online allows them to be served relevant ads. Without it users will still see ads but they will be less relevant to them.

One unwelcome side effect of the move could, however, be attracting renewed attention from regulators who are concerned about the influence Google, the world’s biggest advertising company (Meta is the second biggest) wields over the digital advertising sector and digital economy.