Rhodri Marsden: The software firms are delighted. But Apple's customers are not

It was an odd moment. Apple's Steve Jobs, a man we normally see unveiling gadgets to coos of delight, revealed that his "next big thing" was something most of us view as a colossal irritant: advertising. It was like an airline announcing a new policy of exceptionally bumpy landings. You could almost hear people thinking: "Why are you doing this to us, Steve?"

But software developers are delighted. The public supposition that digital information and entertainment shouldn't cost anything meant that many developers felt obliged not to charge for their iPad and iPhone apps, and previous methods of embedding advertising in them were awkward and inelegant – not least because tapping on one took you away from the app.

An iAd, however, is a less intrusive, easily-minimised "app within an app". With an estimated one billion advertising opportunities per day, it's little wonder the traditional print media – for whom iPad apps have been portrayed as a godsend – are tentatively upturning their plummeting revenue graphs.

Google aren't too happy. The undisputed kings of online advertising now find themselves playing second fiddle to Apple on the iPhone platform, and will continue to do so even if their prospective purchase of mobile advertising company AdMob is approved by the Federal Trade Commission.

But it's iPhone and iPad users who will have to deal with these ads, and their reaction has been predictably unenthusiastic. As a peace offering, developers may offer two versions of apps – one free with advertising, one paid for without – so one effect of iAds might be that we pay in full for our software to banish them from view. Either way, developers win.

With customer ratings highly visible within the App Store, developers who choose to implement ads but do not do it sensitively will soon feel the heat, so the market should eventually determine what we find tolerable. But for some, the idea of being marketed at on a device that accompanies them everywhere – and, indeed, knows where they are – will always be a step too far towards a Minority Report scenario.