Here's how easy it is to install an ad blocker on your iPhone

The latest version of Apple's mobile operating system, iOS 9, lets users download ad blockers to block ads from appearing on mobile websites. That's causing publishers to freak out because they could see a big loss of revenue if lots of their readers on iPhones start blocking ads.

Ad blocking isn't actually available to everyone right now because iOS 9 is still in beta. But anyone with a recent iPhone or iPad can download the beta release of iOS 9.

We signed up to test an early version of an ad blocked called "Freedom." The apps aren't available in the App Store yet, but developers are signing up handfuls of users to test them.