Often users were not notified and had no ability to opt out; an investigation in 2011 found that some apps could break Apple’s GPS access rules. Until recently, app makers could also access users’ unique identifying numbers without permission and therefore track the same users between different apps. 

That unlocked powerful advertising techniques that helped many small apps get a foothold, but also created a grey market for smartphone usage data and let giants such as Facebook build up detailed profiles of users’ interests and habits without their knowledge.

These practices also exacerbated compulsive smartphone use, because every new piece of information that apps collected made it easier for them to keep users engaged with personalised content. 

Facebook’s data let game apps go ‘whale hunting’, targeting specific individuals who were most likely to spend money whether it was good for them or not. 

To Barnard, Apple has ultimate responsibility for all of this because it runs the app store so tightly. ‘Whether or not they specifically deserve blame for the rise of these manipulative free-to-play games, they consciously allowed it by not changing the rules,’ he says. ‘[But] they’re financially incentivised to not stop the addiction.’

As smartphones’ power grew, society began to reshape itself around them. Gloria Mark points out how much of our phone use is reinforced, even mandated, by social conventions, from the expectation that we’ll check emails throughout the day to the common practice of googling to answer someone’s question during conversation. 

We use GPS so much we forget how to navigate; our phones become security cards to our online services; we wait for lifts or buses or traffic lights, distracted all the while.

Nowhere is this clearer than in China, Apple’s primary manufacturing base and now its biggest overseas market. ‘People born in 1980 had minimal contact with laptops,’ says Francesca Yu of AppInChina, a Beijing-based company that helps app makers access the Chinese market. 

‘They are not familiar with office software or internet surfing… [now] everything is done through an app or web page, from purchasing train tickets to paying gas bills. We no longer leave the house with a wallet, ID and a set of keys; instead, we bring only our smartphone and a power bank with us.’ Not just iPhone, but iWorld.

In recent years, Apple seems to have become uneasy with its crown. Having spent the past decade and a half making so many people so thoroughly dependent on its devices, it now faces a perhaps even bigger challenge: taming the forces it unleashed.

It has strained to pare back app makers’ power, presenting itself as a guardian of iPhone users’ privacy and wellbeing. In 2018 it introduced Screen Time, letting people track how long they have spent on different apps, set themselves time limits for each one, and schedule ‘downtime’ when their phone will gently prod them to log off. 

Earlier this year it added Focus, allowing users to define various modes such as ‘driving’, ‘sleep’ and ‘work’, with different notification settings and permissions for each one.

On the data front, Apple finally let users opt out of sharing their unique tracking numbers with advertisers in 2016, and in April this year it began forcing apps to ask permission before accessing them. According to the analytics company Flurry, only 23 per cent of users who are shown such prompts actually agree to them. 

Apple has also promised iCloud customers a virtual private network (VPN) called Private Relay, which will hide their identity from websites they visit, and released a single-use burner email service called Hide My Email. 

Separately, pressure from lawsuits and angry developers has forced it to cut its fees for small companies, and Google has upped the ante by slashing all its fees to 15 per cent.

The new tracking consent prompts are already wreaking havoc on digital advertisers, causing an estimated 15 to 20 per cent revenue drop on iPhones. 

Shares in Facebook, Twitter, Google and especially Snapchat have taken a beating as evidence of the effect trickled out, while Apple’s own advertising business – which is not affected – has seized a commanding new share of the market. 

Eric Seufert, an advertising expert who has written extensively about the crackdown, argues that it will merely push big companies to collect more of their own data rather than obtaining it from others, creating little privacy benefit for users while handing Apple more control.

Mark Griffiths says he is ‘very in favour’ of the new Screen Time and notification management tools because some of them have been shown to work in the British gambling industry, where they are mandatory. 

He believes that smartphones should be subject to similar regulations. Larry Rosen is sceptical, bluntly calling Apple’s features ‘not good enough’ because they offer too little data and are too easy to circumvent. 

Two of his studies tested whether smartphone users could moderate their behaviour given simple strategies; in both, smartphone use actually ended up higher after the interventions.

‘Apple have a really good platform where they could enact change; there’s lots of things they could do… but that’s their business model,’ says Rosen.

‘We’re at the point in this massive paradigm shift where something has to happen from above.’ He wants a massive public information campaign similar to those against cigarettes, but he is not optimistic: ‘We’re just not even close to that… we’re not at the pinnacle yet. We’re just continually spiraling out of control.’