I have a confession to make: I was recently helped home in a police van. They’re surprisingly comfortable inside — all moulded plastic in calming shades of beige — presumably designed to have the same tranquillising effect on their passengers as playing Beethoven to yobs outside shopping centres. But please don’t put me in that category. My only crime was phenomenal naivety. Phone out of battery so I couldn’t order a taxi, no cash for a black cab, and not an ATM in sight, I had lost a wager with technology and, if it wasn’t for the pity of a policewoman, I risked spending the night wandering a dangerous part of London — or worse.

Increasing numbers have stories like this to tell — a sudden realisation of the fickleness of the amazing new services that have made our lives immeasurably more convenient, but have left us less resilient and more dependent on the kindness of strangers when all goes wrong. Abandoning cash for contactless credit cards seems straightforwardly sensible, for example, until your bank’s IT systems go under, a criminal steals your details, or you realise your every transaction can be scrutinised by unknown eyes. Many of us couldn’t get by without GPS. What happens if the system fails and you’ve binned all your road maps?

But this is only half of it. We’re losing another bargain with technology — by giving away too much about ourselves on trust. The taxi app Uber has revealed that the information of 57 million customers has been exposed, probably by Russian hackers. The company claims there is “no evidence” of fraud as a consequence. And despite a spate of similar breaches at companies as diverse as Talk Talk and Yahoo, it is unlikely that even such a disastrously lax attitude to security will in itself radically change how consumers view the digital economy. In any case, new regulations are being introduced to tighten up how our data is handled. But these hacks do make plain quite how vast, and growing, are the quantities of information such companies retain about us. Uber keeps email addresses, phone numbers, bank details, dates of birth and journey histories. Google and Facebook will have more than that; enough to build disturbingly accurate pictures of who we are, who we love, what we like.

Self-evidently, consumers don’t want absolute privacy if it means losing access to the internet. It may rarely be made explicit, but most of us are dimly aware that we’re engaged in a transaction: for free use of a service, we let them collect information so that advertisers can sell us targeted products. But the technology giants have become arrogant. Google has admitted that it has been tracking its customers’ movements via their smartphones, even when they have disabled the function that permits the company to do this. It has said it will update the phones to prevent this from happening again, but can we really rely on such companies not to trample on our privacy if they can find a commercial justification to do so? The transaction between individual and tech giant is also becoming increasingly difficult to opt out of. The industry is charging ahead into an exciting future of “connected” devices. The world will soon be littered by sensors, your household appliances hooked up to the internet, while employers are experimenting with “wearables” to track their staff. As these items proliferate in homes, shops and offices, it will become harder to withdraw consent from being monitored. Who will not chafe at the potential for snooping that this implies?

And, data breaches aside, can we trust the tech giants themselves? They like to think of themselves as neutral platforms, but that is no longer true. They intervene in politics — banning people from using their services because of their views, sacking staff for having opinions outside the leftwing mainstream. Facebook’s chief executive is even said to be plotting a run for US president. There is only so much regulation can do to stop data being misused for nefarious ends by companies with an agenda.

Technological advances are almost always an unalloyed good, but we must wise up to the implications of sacrificing control of so much of our personal information. The alternative doesn’t bear thinking about.

— The Telegraph Group Limited, London 2017

Tom Welsh is deputy comment editor at the Telegraph.