Mobile Internet sites face a new threat as millions download ad-blockers to their phones and tablets, removing pesky adverts but potentially wiping out billions of dollars in advertising revenue.
There were close to 200 million downloads of ad-blocking software by mid-2015, according to research firm PageFair, but only 1.6 percent of the blocking was done on mobile devices rather than computers.
That could be changing as mobile ad-blocking software becomes increasingly popular across the globe, particularly after the high-profile move by Apple to incorporate it directly into its latest iPhone and iPad operating system iOS9. The software tends to be cheap and effective.
Quickly installed, it reduces the clutter on web pages, speeds up performance and spares users from some of the click-bait that many find hard to stomach. "When people are even willing to pay to stop adverts, it gives you an idea of how fed up they are," said Hicham Berrada, head of France de Teads, a video advertising firm.
While the Chinese government trawls websites for politically sensitive content, they remain littered with pop-up advertising, forcing millions to buy apps such as "360 Mobilephone Guard". In Hong Kong, mobile ad-blockers "Purify Blocker" and "Crystal" recently entered the top 30 paid-for iPhone apps.
A study by Adobe and PageFair in August said the losses for websites that rely on advertising could be huge -- totalling an estimated $21.8 billion (19.3 billion euros) this year and rising to $41 billion in 2016. But few mourn the loss of nuisance publicities, with Hong Kong tech site Unwire.hk recently promoting the blocking apps even though the magazine itself relies on advertising revenue.
"As an employee of Unwire, writing this tutorial does not do good to the boss's livelihood, but I also understand some people do not have unlimited data plans and it's a pain to be receiving data-consuming ad banners," said reviewer Tim Yan.