The next version of Apple‘s Safari mobile browser will make it possible for third-party extensions to block mobile web ads on iPhones and iPads.
The changes were confirmed Friday when Nieman Journalism Lab discovered new “content blocking” provisions in the developer documentation provided by Apple for its upcoming iOS9 update. According to Apple’s documentation, content blocking gives developers working on third-party Safari extensions “a fast and efficient way to block cookies, images, resources, pop-ups, and other content.”
Although Apple has not announced any intention to enable ad blocking, it’s likely that ad blocker extensions like Adblock and Adblock Plus will be able to use content blocking to prevent ads from being served on sites that Safari mobile users visit.
Ad blocking has taken off among consumers on desktop devices. According to anti-ad blocking organization PageFair, the number of adblock users globally grew 70% between June 2013 and June 2014, and there are now 144 million online users who employ some kind of ad blocking technology.
But ad blocking has been technically difficult to accomplish on mobile, where Apple and Google keep tighter controls on what modifications third party apps can make to their browsers and OS settings.
By adding content blocking on Safari’s mobile version, Apple may be loosening those restrictions enough to let enterprising ad blockers gain a foothold in the iOS ecosystem.
However, it’s important to note that the changes only make it possible to block ads on mobile sites, not on apps the user has downloaded, and that content blocking will also facilitate lots of other applications, like blocking tracking scripts for privacy reasons.
The development has some publishers worried that ad blocking could begin eating into their mobile revenues, just as it has on desktop. PageFair recently estimated that ad blocking costs Google alone $1.7 billion per year.
Apple did not announce Safari’s new content blocking feature at last week’s WWDC conference. However, earlier this month, CEO Tim Cook took aim at publishers and online data collection companies that use personal data for advertising, arguing that they are wantonly violating consumers’ privacy.
“I’m speaking to you from Silicon Valley, where some of the most prominent and successful companies have built their businesses by lulling their customers into complacency about their personal information,” he said. “They’re gobbling up everything they can learn about you and trying to monetize it. We think that’s wrong. And it’s not the kind of company that Apple wants to be.”
