The most important tech of the 21st century – according to Which? experts

From the millennium to now, tech has bound itself to every aspect of our lives, like ivy on a garden fence. It’s essential, transformative, problematic and there’s no going back.

With the help of tech experts across Which?, we’ve narrowed down the dizzying array of 21st-century technology to 15 innovations we feel have truly defined the past few decades. For better or worse, these devices, programs and inventions have changed the way we live forever.

Below, we run through our initial list of 15-8. Bookmark this page and check back next week, 5 February, to see which tech made it to our pick of the top seven.

15. BBC iPlayer

The idea of appointment television – households gathering at a set time for a long-awaited series finale, phone off the hook, a chorus of shushes as the adverts end – is effectively over. Broadcasters once set the timetable, but not anymore. When the BBC launched its catch-up service in 2007, it put the viewer in charge of the schedule and was one of the early pebbles that became a streaming avalanche.

Unless you recorded TV onto video cassettes, DVDs or a PVR, you had no chance to watch a show. Evening plans, schedule clash, someone else using the TV? Sorry, you’ve missed it. It seems archaic now, as iPlayer gives you weeks to watch whatever you missed in your own time.

ITV, Channel 4 and Channel 5 soon followed suit, and catch-up TV was born. Amazing shows are still getting made, thrilling finales are still being discussed, but you make the appointment to watch.

Enjoy your favourite shows on a TV with dazzling picture quality – see our round-up of the best TVs to suit your budget.

14. Uber

'Should we get an Uber?' Pre-2012 this was a meaningless phrase, but an ingenious app and a fleet of Toyota Priuses made it common parlance. Its introduction has been far from smooth. From resisting drivers’ right to a minimum wage (until the Supreme Court ruled otherwise) to its effect on traditional taxi companies, Uber is controversial, but that hasn’t dulled its popularity.

Being able to see a fixed price for the journey and know the car's location on a map, as well as the name and face of a registered driver before you get in the car, gave Uber the edge over black cabs and local firms.

It spawned competitors, but no one’s saying 'should we get a Bolt?'. Uber is genericised: to many people it now means taxi; that's unlikely to change.

13. Nintendo Wii

Depending on who you ask, back in the day a video game controller was an intuitive conduit to fun or a barrier to entry. The collection of colourful buttons might as well have been a 747 cockpit to some, and it reinforced the idea that console gaming wasn’t for them. Nintendo, ever the innovator, saw this problem and fixed it.

While traditional controllers looked like Formula 1 steering wheels, the Wii controller had more in common with a TV remote. It felt familiar to all, even before Nintendo played its trump card. Wii Sports came packaged with every console, and it masterfully took advantage of the Wii’s headline feature: motion control.

The ‘Wiimote’, as it was known, became a tennis racket, a golf club, a bowling ball and more. The intuitive joy of seeing an avatar mirror your movements, whether smashing an ace or rolling in a strike, is a moment that broke down barriers and preconceptions decades in the making.

The Wii made gaming for everyone, and it went on to sell more than 100 million consoles.

See our pick of the best gaming deals covering Nintendo, PS5, Xbox and more.

12. Video streaming

When the clock struck midnight on 1 January 2000, most people in the UK had access to five TV channels. Fixed schedules, five options – with no swearing, violence or sex before 9pm. Streaming tore up these rules.

It was on-demand viewing. No schedule, no programme guide – just a catalogue of drama, documentaries and films only a search away. Even with Freeview bringing more channels, broadcast TV is a tuck shop with a few sweets, while streaming is Willy Wonka’s whole factory.

The cornucopia of choice catering to all tastes made streaming services some of the country’s biggest success stories. At 300 million, Netflix has more subscribers than there are people in the UK, France, Germany and Spain combined. Many rivals aren’t far off these figures, either.

Streaming was a significant part of the immediacy culture that defines the past 26 years. We want choice, and now.

See our guide to the best and worst TV streaming services to find out which one real customers think is best.

11. AI

This will be a bigger fixture of the next 25 years, but even in its infancy, artificial intelligence is already making big ripples. The world’s biggest software companies have done a good job of injecting it into the software and devices we use most, and now they need to develop trust and show us why we should care.

The likes of ChatGPT and Q are useful tools whose programmed quest to pander and please can lead to them giving incorrect information. Copyright questions and the potential loss of true creatives to AI limitations are problems that must be ironed out, but the limitless possibilities of AI mean it’s here to stay.

Unleashing astonishing processing power with the ability to learn, adapt and problem solve will yield incredible results – as long as humans retain oversight. It’s already changing the world, and it’s not done yet.

See our investigation: Can you trust AI? ChatGPT and other AI chatbots tested, plus learn how to avoid AI scams.

10. NFC

Near Field Communication might be the most unassuming thing on this list – an invisible connection that allows you to pay on a card reader with your phone, watch or card without a Pin. It’s the ubiquity that makes it important.

It was adopted without much fanfare, helped by a reluctance to touch keypads and cash during Covid-19. Initial concerns around theft lost out to convenience, and now it’s the norm. We tap and we go.

9. Social media

Almost half the global population actively uses Facebook, owned by parent company Meta. Three billion people uploading photos, joining clubs, selling unwanted items and organising gatherings. In its purest form, it connects people and offers a platform to share thoughts, jokes and art. At its worst, it’s a tool used to spread dangerous disinformation, test scams, prey on the vulnerable and spread vitriol under the protection of anonymity and free speech. Facebook is wonderful and terrible – as is all social media.

While Facebook morphed from catching up with friends to a source of news, Twitter was always designed to be a hotbed of discourse on current affairs in a bite-sized format. When Elon Musk took over, he said Twitter (renamed X) was 'the digital town square where matters vital to humanity are debated'. His tenure has seen a spike in hate speech on X, with problematic voices seemingly welcome in the square.

Social media sits at the heart of our always-online culture. It’s intrinsically linked to so many important aspects of modern life, it’s no wonder so many people use it every day and will continue to do so.

Lock up the data you share online – learn how to secure your social media and email accounts.

8. Mobile internet

Mobile internet is a map in unfamiliar surroundings, a taxi in the rain, a recipe in the supermarket, a translation when abroad, a how-to video next to a broken down car. It’s entertainment, information and everything else on the go.

So many entries on this list owe 3G, 4G and 5G a debt of gratitude – mobile internet is the great enabler and easily one of the most life-changing developments in recent memory.

To uncover the best and worst UK mobile networks, we asked more than 4,000 members of the public to tell us about the networks they love – and the ones they hate.

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