A new feature buried in the developer documents for iOS 9 suggests Apple is building in support for ad blocking and privacy apps, with a new API that removes elements from Web views.

The new “Content Blocking” feature allows developers to pass a JSON file with a set of rules for images, popups, cookies, resources and other elements in Safari.

Content Blocker is live in iOS 9 beta builds right now, with the menu option explaining that “Content Blockers affect what content is loaded while using Safari” but offering no options until an app that adds blocking functionality is deployed.

Such a feature would allow apps like Disconnect, which blocks tracking scripts around the Web, to exist on iOS for the first time since launch.

Apple doesn’t supply in-depth detail about the new content blocking feature right now, but it’s also supported by Safari on OS X in the upcoming El Capitan release.

It’s unclear what Apple’s motivation could be for encouraging ad blocking on the Web.

As it runs its own ad network, iAd, it may be a strategy to push websites that rely on ad revenue into building native apps instead, where it can get a cut of the advertising revenue and guarantee they’ll still appear.

We’ve asked Apple to clarify what it’ll allow Content Blockers to be used for and if it’ll accept ad blocking apps onto the App Store when iOS 9 is available later this year.

➤ What’s new in Safari [Apple Developer]

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