NEW YORK: The imminent launch of a new Apple mobile operating system, which is expected to give users access to ad-blocking facilities, is focusing the minds of publishers who fear they will soon be taking a financial hit.

"The ad-blocking problem is real and growing, and ad blocking on iOS is only going to accelerate it," Jason Kint, CEO of Digital Content Next, a digital publishers' association, told the Wall Street Journal.

And Sean Blanchfield, chief executive of PageFair, a provider of ad-block solutions to publishers, concurred. "Apple is going to create a massive consumer appetite for blocking ads," he stated.

A joint report from Pagefair and Adobe recently described ad blocking as a "viral phenomenon" that posed an existential threat to the future of free content on the web.

It said that 198m people were using adblockers in June 2015 and suggested that ad blocking globally would lead to lost revenues of $21.8bn in 2015, rising to $41.4bn in 2016.

That figure could be an underestimate if millions of iPhone and iPad users take advantage of iOS 9 and install apps that prevent ads from appearing in its Safari browser.

Crucially, Apple will not be allowing ad blocking within apps, because ads inside apps do not affect mobile performance in the same way they do on in a browser. The developer of one iOS 9 ad-blocking app reported that it could reduce browser page load times by 70% or more.

When commentator John Naughton visited the popular Mail Online site he reported finding a total of 31 third-party trackers and cited separate research showing that actual content on a page of one well-known tech site amounted to 8kB while surrounding ads ran to 6MB.

"There's no doubt online advertising is ruining the web experience for many users," he said.

Dean Murphy, developer of the Crystal ad-blocking app, said his creation was exactly the kind of app Apple wanted when it went looking for Safari extensions. "I can't think of any other use for it other than blocking adverts, JavaScript and cookies," he told AdExchanger.

The Wall Street Journal noted that Apple already has a business serving ads inside apps and that the new operating system would include an Apple News app hosting articles from major news publishers. Apple is likely to get a share of any revenue from ads accompanying those articles.

Data sourced from Wall Street Journal, Ad Exchanger, The Observer; additional content by Warc staff