Brian Cullinan had one job. It was the LA-based accountant's responsibility to make sure that the right envelope got into the right hands at the right time during Sunday's Oscars ceremony.

For the PwC managing partner and chairman of the accounting firm's US board, it should have been a doddle. Cullinan's day job presumably involves carrying off vastly more complex feats than something eight-year-olds distributing birthday party invitations manage to do without too much drama every day.

And judging by his Twitter feed, his role at the Oscars is not one he or his partner Martha Ruiz takes lightly. He started tweeting about the ceremony as early as December, and has said in interviews that preparations for the voting start for the following year in March.

“I have all 24 envelopes in my briefcase; Martha has all 24 in hers. We stand on opposite sides of the stage, right off-screen, for the entire evening, and we each hand the respective envelope to the presenter. It doesn’t sound very complicated, but you have to make sure you’re giving the presenter the right envelope,” he said in a recent interview.

He’s right: it doesn’t sound complicated. But as the world is now aware, Cullinan messed it up, catastrophically and at the very worst moment. He handed the envelope for Best Actress to Warren Beatty, and in that instant condemned himself to instant memedom and a lifetime of introductions as ‘The Guy Who’.

Even after he must have heard the wrong film being announced, it took over two minutes for him to appear, red-faced, on stage and hand the real ‘Best Picture’ envelope to an incredulous Beatty.

It took less time than that for a plausible explanation for the error to emerge. Cullinan, it seems, may have been suffering from smartphone distraction. The Wall Street Journal discovered that, right about the time he should have been concentrating on getting the Best Picture envelope to Beatty, he was busy tweeting a photo of Emma Stone backstage (a tweet he subsequently deleted.)

It’s tempting to write about how smartphones have turned us all into reckless, rude teenagers, incapable of concentrating on anything else when there’s an amusing tweet to be dashed off, a selfie to be taken, a Snap to be sent.

But that’s not true. In fact, they have turned us into toddlers – freewheeling thoughtlessly through our lives in search of the next diversion, incapable of delaying gratification even for a second when there’s a brightly coloured button to be pushed, a post to be liked, a link to be clicked or a screen to be swiped.

It is safe to say that White House senior adviser Kellyanne Conway is not someone most of us would turn to for etiquette advice. Even so, it was jarring to see the photos that emerged from the Oval Office last night, showing her kneeling on a couch with her shoes on, jabbing at the screen of her phone, oblivious to the perturbed gazes of the leaders of historically black colleges who surrounded her.

She reminded me of someone, but for a second I couldn’t think who: the awkward, splayed legs; the rigid index finger; the complete lack of self-awareness; the total concentration on the screen in front of her.

Yes, it was my toddler.

Cullinan and Conway are just the most visible recent examples of the extent to which the compulsion to pull out our smartphones at the most inappropriate moments has become completely normalised. We appear to be evolving into a species whose impulse control centre now resides somewhere between our thumb and our index fingers.

Our phones are like slot machines in our pockets, exerting an irresistible, magnetic pull on our attention. As technology gets more sophisticated, delivering more and better feedback in the form of a seductive and unpredictable pattern of sounds, lights and noise – the little details that bring the experience to life, referred to by game designers refer to as “juice” – we become more deeply enslaved to it.

Once, the suggestion that people would risk their own and their family’s lives rather than miss out on a text might have seemed entirely ludicrous. But you have only to talk to a garda or read coroners’ reports of road traffic accidents to discover that, tragically, it’s all too commonplace.

The irony is that there’s no real pleasure in this enslavement to technology. A recent study by Deloitte found that 18-24-year-olds check their phones, on average, every 20 minutes.

Another survey of 3,500 adults by the American Psychological Association found that these “constant checkers” reported higher levels of stress than people who spent less time online. One in five of those surveyed said that technology stresses them out. Two thirds agreed it was important to detox frequently; only 28 per cent had ever actually done so.

I sat down to write this piece with my phone just beyond the reach of my left arm. Three times, in the course of writing about smartphone compulsion, I found myself compulsively reaching for my own smartphone. I didn’t have any messages to send or pithy tweets to compose: in fact, like Brian Cullinan, I had only one job, and none of it involved my phone. Still, anyone of us who have ever given into the gravitational pull of their device can take solace from the fact that however bad we might feel, there’s at least one person out there who feels much, much worse.

Tim Ryan, Brian Cullinan’s boss at PwC, spent the early part of this week offering the firm’s profuse apologies to the Motion Picture Academy, to the filmmakers behind the two movies and to Warren Beatty.

“I have reached out to the Academy and shared with them that we take full responsibility that Brian had made the mistake and the firm takes responsibility for that,” he said in a statement known in corporate parlance as “throwing Brian under the bus”.

"We are very proud of being associated with the Academy Awards. It's good for our brand. It's good for our people. So while I am concerned I hope we will be judged on how quickly we reacted and owned up to the issue," he added, perhaps a tad optimistically.

Ryan said he had spoken to Cullinan about the episode “at length”. “He feels very, very terrible and horrible. He is very upset about this mistake.”

When the reissued, low-tech Nokia 3310 comes out in LA, it’s probably safe to say Brian Cullinan will be at the top of the queue.