iPhone iOS 9 adblocking
Content blockers can strip away ads, tracking cookies and scripts on websites viewed through Safari on iOS 9. Reuters/Adrees Latif

One of the much-touted features of iOS 9 is the ability to block content, such as ads in the Safari Web browser. And in the wake of the release of Apple’s latest mobile operating system, apps designed to block ads have soared to the top of the App Store's paid download list.

Peace, a $2.99 ad-blocking app designed by Tumblr co-founder Marco Arment, took the top spot, dethroning Microsoft’s ever-popular “Minecraft.” Similar apps also broke into the top of the paid app charts. Purify, another $3.99 content-blocker designed by developer Chris Aljoudi, sits at fourth place. And the $0.99 Blockr app rose to 17 as of Thursday morning.

Once downloaded and set up, the apps remove ads and JavaScript from websites viewed through the built-in Safari browser. But this doesn’t apply to other third-party browsers, such as Google’s Chrome and Opera mini, or ads displayed in various apps.

Ad Blocker iOS 9
Content-blocking apps rose to top spots within Apple's App Store. Illustration/Luke Villapaz

The move to support ad blocking in iOS 9 is a concern for Google and website publishers, which make most of their revenue from Internet ads -- more specifically, mobile and desktop browser ads. But it’s unlikely to affect social media companies such as Facebook and Twitter, which rely more on ads within their own apps.

To get around content-blocking apps on desktop, companies such as Google, Amazon, Microsoft and Taboola even paid off the developer of Adblock Plus to whitelist their ads in February, according to the Financial Times. Despite the introduction of ad blockers to iOS 9, mobile ad spending is expected to rise 61 percent to $68.7 billion globally, according to eMarketer.