While Android devices have access to apps and tools that block ads from being displayed in apps and websites, the same cannot be said for iOS. While OS X allows extensions such as AdBlock to be installed on Safari, this is a feature that has yet to be introduced to the iOS version of Safari, at least not until now.
It seems that come iOS 9, Apple will allow app developers to create content blockers for the mobile version of its browser. As you can see in the image above, these content blockers can be loaded in Safari and will allow users to define what kind of resources they would prefer Safari to not load, such as images or scripts.
While it does seem like a way to allow webpages to be loaded faster, since disabling images and scripts would just load the content only, it could potentially be used as a means to block ads from displaying, which at the same time could be Apple’s way of taking a shot at Google as the latter typically relies on ads to make money.
It also seems to be in line with Apple’s new News app which will be a Flipboard-like app that will display news and will also be able to curate content based on the topics and articles that you might have read in the past. Presumably the content blocking feature will not affect the app, thus giving advertisers incentive to advertise in Apple’s app instead of Google.