The dramatic take-up of ad-blocking software by Australian online users is quickly approaching 4 million, outnumbering Twitter's base in Australia and triggering warnings of a shake-out for advertisers and digital media companies. 
Apple's iOS9 Safari web browser update in   September will also include an ad-blocking option which British Vogue's digital creative solutions manager Emma Geary has described as the "most disruptive update yet" and arguing Apple is "strong-arming publishers into examining revenue models that diverge from the traditional ad banner business".
There are also implications for blue-chip advertisers who are swinging advertising investments out of print and broadcast TV to digital channels.
Apple's new Safari release will block online pre-roll video ads, a rare booming part of the media industry which is exciting advertisers looking to shift dollars out of broadcast TV.
Figures released by Dublin-based PageFair will also challenge views in the Australian market that ad-blocking is not as prevalent here as it is in European and American countries - more than 150 million users globally now have ad blockers installed, up from 54 million users two years ago.
PageFair will release updated figures globally on Monday and for the first time it has analysed the Australian market, which will make for uncomfortable reading. In less than two years the number of users with ad-blocking code installed in their web browsers has nearly doubled along with penetration now sitting at about 18 per cent of the online Australian population. Ad blockers essentially prevent publishers from serving ads with their content.
The chief executive of online youth-skewing publisher Junkee Media, Neil Ackland, said public annoyance with interruptive advertising and personal privacy concerns was contributing to the take-up of ad blockers.
"The reason the Safari update is so significant is it accounts for 42 per cent of all mobile web browsing and our audience is 70 per cent mobile. When you start doing the math, if it takes off it and becomes a key feature of iOS and Android it could have a decent dent on what's going on. For us it places more importance on being a premium publisher with a mature native advertising model."
Native advertising involves brands and publishers producing less traditional advertising display and video formats, instead creating editorial style content designed to sit within editorial streams with less hard sell messaging.
The AWOL content venture between Qantas and Junkee for younger travellers is a case in point - Mr Ackland said AWOL saw a record number of users last month.
Seven West Media's chief digital officer Clive Dickens played down the ad-blocking impact of the Safari update.