The conversation surrounding iOS 9, Apple's latest mobile operating system, has revolved around its new support for ad and content blockers. The new apps have caused a stir up among the digital publishing industry, with many wondering what the fate of the internet will be if the ad revenue stops flowing.

At present, a blocker by the name of Crystal sits atop the app store's best seller's list. The Wall Street Journal reports that Dean Murphy, the developer behind Crystal, has already earned about $75,000 from his creation.

The app has run into a bit of controversy however, as the paper revealed that it is also receiving payments from companies that want their ads to get through Crystal's filtering.

Crystal has teamed up with Eyeo GmbH, the company behind Ad Block Plus, the leading blocker on desktop computers. Eyeo has an 'acceptable ads' policy that allows ads which do not impede on a user's browsing experience to make it through the blocking software. Companies that want to get into this 'whitelist' must pay Eyeo in order to do so.

"Given how popular Crystal has become, it doesn't provide any way for users to support publishers," said Dean Murphy to the WSJ. "I decided that's a good feature to provide, and from what I've seen the 'acceptable ads' policy doesn't let through what I'd classify as bad ads."

The acceptable ads feature can be turned off by users entirely, but it has sparked a bit of a debate among critics.

Is it ethical for a company to sell a service that purports the blocking of ads, then charge money to advertisers in order to let those same ads through? Matt Buchanan of the Awl puts it bluntly:

'If your adblocker takes money from you in order to block ads, and then takes money from huge companies in order to show you the ads that you paid for it to block, then yes; it's just using you to erect a tollbooth.'