Steve Jobs, Apple's co-founder, was prone to hyperbole but his eulogy for the iPhone as he launched it 10 years ago was accurate: "Every once in a while, a revolutionary product comes along that changes everything."

Google was just an internet search engine then, but one of its offspring unveiled plans this week to make an entire platform – software and hardware – for driverless cars. Without the iPhone revolution, it is hard to imagine a technology company entering the transport industry, or designing a device that can steer cars around while receiving and transmitting streams of data.

For a long time, Jobs was a lone voice in the wilderness in preaching the power of uniting hardware and software, while Microsoft made a fortune by dominating software alone. Even he did not predict the potential of integrating everything from software and mobile hardware to data storage and artificial intelligence. Yet this is his legacy: the omniscient tech company.

It was difficult in 2007 to imagine what such an enterprise could be worth. Only Microsoft was among the world's 10 most valuable companies, not Amazon, Apple, Facebook or Google. The latter ranked 51st in the FT Global 500 in the first quarter of 2007; Apple was 85th, Amazon did not make the list and Facebook was still five years away from its initial public offering.

These five companies, with Google renamed Alphabet, are all in the top 10 now. Information technology has become the dominant source of corporate value, displacing finance, telecoms, and energy. "Mastery of data is like the steam engine of our age," says Annabelle Gawer, professor of digital economy at the University of Surrey.

Its impact on other industries is obvious in transport. Carmaking was once vertically integrated: Henry Ford controlled the raw materials that went into his cars, along with their assembly and distribution. The industry's scope has since narrowed, and technology is steadily dismantling it.

Waymo, Alphabet's driverless car company, this week displayed its new sensors on Chrysler minivans: Sergio Marchionne, Fiat Chrysler's chief executive, does not think that carmakers should try to beat technology companies at their own game. Ford is letting Amazon put Alexa, the artificial intelligence software that powers its Echo home assistant, into Ford cars.

The impact is also clear in retailing. Amazon's relentless rise – its market capitalisation has grown from $16 billion at the time of the iPhone launch to $380 billion – is squeezing bricks-and-mortar retailers. Sears and Macy's, the US retail chains, unveiled further store closures last week; both have invested in technology to increase online sales but are struggling to beat Amazon.

The new breed of tech company has three competitive advantages (leaving aside tax and regulatory arbitrage). The first is scale: they employ thousands of engineers and operate networks of server farms – and in Amazon's case retail warehouses – that smaller rivals cannot match. Like other conglomerates, they have deep resources.

Second, less traditionally, they exploit network effects. No matter how many people buy Fords, its cars work the same. This is not true of Google's search engine or Facebook's social network and messaging applications. The more users they amass, the more data they can collect and the better the service becomes. It creates a virtuous circle.

Last, they are becoming vertically integrated – the strategy that Jobs brought to Apple. They make hardware, from Apple's iPhone and Google's Pixel to Amazon's Echo, and are finding new ways to put sensors in other devices, such as driverless cars. By analysing the data these capture, they can develop products tailored to every user.

This raises the question of whether such huge power must be curbed. Their handling of data has to be regulated since it is easily abused – safeguards are needed, such as Waymo's effort to stop vehicles being hacked.

Are they already so dominant that antitrust authorities should break them up?

Not yet, I think. It is easy to forget how recent – dating back only a decade – their emergence is. Their story is still playing out: Waymo's technology is still being developed and Amazon's success with the Echo only partly makes up for its failure with the Fire phone. Silicon Valley is littered with companies that once appeared all powerful but later stumbled, including Yahoo.

In another decade, things could be different: they may lose focus in trying to mimic each others' strengths, as conglomerates often do. Companies tend to be good at some things and bad at others: a corporate software giant does not design the most exciting consumer devices. Microsoft spanned many businesses with patchy results before focusing on cloud computing.

But vigilance is needed. The combination of forces that fuelled the rise of such companies has no exact historical precedent: a technology revolution has created new economies of scale. Apple's Jobs outflanked Microsoft with the iPhone but his rival remains strong; the power of others could yet grow.

john.gapper@ft.com