There is, alas, no such thing as a free lunch. What’s even more depressing is that there is no such thing as a free internet service. Most people nowadays probably understand that in relation to, say, social networking services, if the service is “free” then the users (or, more precisely, their personal data) are the product. But this also applies to stuff that you haven’t signed up for – websites that you browse, for example. The site may be free to view, but there’s often a hidden cost.

One part of that cost comes from surreptitious tracking of your browsing habits by outfits that sell that information to advertisers. (If this is news to you just install the Ghostery browser extension to see who’s monitoring your browsing.) The other cost comes from ads that are placed on a webpage either directly by the site owner or as the outcome of a real-time auction that goes on in the depths of the internet.

And as the web has evolved, and more of our lives conducted online, internet advertising has steadily increased. It’s now at the stage where it’s really annoying. Webpages that used to load relatively quickly suddenly take ages to appear. Videos pop up unannounced and – worse still – start to play without your consent. And there’s a lot of hidden downloading going on before the page finally appears. Scrolling down becomes unaccountably jerky. And so on. This is bad enough on fixed-line connections; on mobile connections it is truly infuriating – and it eats into your data plan as well.

So it’s not surprising that internet users have been going for ad-blocking software like ostriches go for brass doorknobs (as PG Wodehouse would put it). One report claims that ad-blocking has grown globally by 41% and in the US by 48%. Since these estimates come from sources that have vested interests in this area, they should perhaps be taken with a pinch of salt, but there’s no doubt that ad-blocking is now a big deal.

Illustration by Matt Murphy.

And, as with all of these things, it’s led to an arms race between those who create ad-blockers and the people whose products they seek to exclude. But now Apple has stepped on to the battleground. The new release of its iOS mobile operating system contains some hooks that enable programmers to create apps that block content (aka ads) within the Safari mobile browser. Last time I looked there were nearly 20 of them available on the App store.

Because Apple is such a dominant company, this new ad-blocking technology has stirred people up. My hunch is that the impact of the iOS change itself will be relatively small: the iPhone is very profitable, but it has only about 15% of the global smartphone market, and the content-blocking facility only works on the newest model – the iPhone 6.

The real significance of the Apple development is that it puts the weight of a giant company behind the idea of content-blocking, which means that the use of ad-blocking software is likely to accelerate. And this, as Jean-Louis Gassée (a former Apple executive, incidentally) points out, might be a mixed blessing.

“The good news: we’ll soon have ways to streamline our browsing experience and avoid being pimped to advertisers. The bad news: marginally profitable websites, which is most of them, will lose advertising revenue and plunge into the red. The big guys that have paywalls in place, sites such as the New York Times, Financial Times, or Le Monde, will be much less vulnerable.”

Pervasive ad-blocking will dramatically undermine the predominant business model of the “free” web, which is that the price of freedom is exposure to ads. Without those ads, online publishers will have to find a new business model or go under. And currently, there are not that many alternative models out there.

One is the subscription/paywall route – the option that the publishing giants mentioned by Mr Gassée are already employing with considerable success. But that option is not available to most of the smaller publications that are the glory of the web and enrich the public sphere. For them, donations are probably the only way of paying the hosting and other bills. And, as all charities know, donations can go down as well as up.

The rise of ad-blocking will force us to confront the fact that the free lunch provided by advertising is not long for this world. The good news is that the ensuing crisis will compel us finally to look for what we should have invented decades ago, namely sustainable business models for the web. For example, it’s possible that cryptocurrencies might enable the “micro-payments” that would make users to pay a tiny amount for any article they read. We need more ideas like that, and I’m sure we’ll get them. Necessity is the mother of invention.