Mums everywhere are sharing this story about teens and smartphones with good reason.

When you’re a parent there are certain worries about your children that – eventually – resolve.

You worry they will never sleep through the night – and then, almost miraculously, they do.

You worry they will ever stop inverting their letters when they first start to write – and then you spy that perfect B.

You worry they will never make a friend at their new school – then this boy called Josh is sitting on your couch, eating all your Barbecue Shapes.

Then there are worries that seem to grow more complicated. Worries that act like a persistent itchy skin disease inside your mind. They are always there, some days you don’t notice them so much, other days they take over.

You worry about whether they are building resilience.

You worry about what kind of world they will live in.

And you worry what the hell those smartphones are doing to them?

I know I’m not the only one who is developing a growing unease with smartphones. I’m not a psychologist, I’m no researcher, I’m not a doctor or even a candlestick maker, but I can’t help but look around me – at cafes and bus-stops, beaches and footpaths – and think too much time on smartphones is not in anyone’s longer term best interests.

Surely engaging with a smartphone is no substitute for engaging with the real world, your own thoughts, your own creativity, nature, friends, family, the dog?

Deep down I know the answer to that. I think a lot of parents know it too. That’s why they are sharing this story across the globe: Have Smartphones Destroyed a Generation.

Written by US psychologist, author and research specialist on millennials, Jean M Twenge, the article forensically examines one of the most potent and pervasive fears of modern parents: what is the technology that our children hold in their hands doing to them? Are we right to be worried this technology – and the accompanying social media – is hurting them deeply and fundamentally?

Twenge has been researching generational differences for 25 years and has researched generations from as far back as the 1930s. The psychologist writes that the characteristics of every generation she has studied typically end up following the same pattern on a line graph: over time the line ends up looking like modest hills and valleys.

She was expecting the same for the generation of teens she began studying in 2012 (these are not millennials - Twenge has called them the iGen). But the graph was wildly different to every one before it. It is a graph full of "steep mountains" and "sheer cliffs" and the academic wondered what has happened since 2012 to cause such dramatic changes in behaviour.

So Twenge investigated.

Her verdict: the smartphone.

Twenge says the impact of devices goes far beyond "screen-time".

Here are Twenge's most interesting findings or musings (but read the article):

• There is compelling evidence that the devices we’ve placed in young people’s hands are having profound effects on their lives—and making them seriously unhappy. It’s not an exaggeration to describe iGen as being on the brink of the worst mental-health crisis in decades.
• All screen activities are linked to less happiness, and all nonscreen activities are linked to more happiness.
• The correlations between depression and smartphone use are strong enough to suggest that more parents should be telling their kids to put down their phone. 
• According to the statistics referenced by Twenge's today's teens are:
• Not hanging out (physically) with friends
• In no rush to drive (a marker of independence)
• They date less
• They have less sex
• More likely to feel lonely
• Less likely to get enough sleep

Yes, the article is alarming and has been condemned and criticised for going too far. Psychology Today said the research Twenge reviews relies on correlation, not causation and that the author has "cherry-picked" her studies.

Lisa Guernsey wrote in Slate Smartphones are linked to problems but they haven't "Destroyed a Generation".

Guernsey is a mother of two teen girls, 13 and 15, and agrees there are issues with smartphones but it's not as bad as Twenge makes out:

"Are social media and the convenience of our mobile devices causing young people to be more depressed? Or, could it be the other way around: They already are more depressed, and they are turning to their phones for solace? Of course there’s also a third possibility: Maybe there’s a nefarious reinforcing circle here. Where is the end, and where is the beginning?"

Okay, maybe we don't KNOW where this end or beginning is. But we can feel that this middle is not right and we can mitigate risk - our children's risk to live a happy, full and rich life by being mindful of the pitfalls of smartphones and social media and then DOING something about it.

Guernsey's article also says: "Parents can’t wrench the phones out of teens’ hands and tell them to go straight back to 1985."

I honestly don't think the reasoning "well smartphones and social media are here now so there is nothing I can do" is good enough. There are international leading psychologists now who won't even pull out their smartphone in front of their baby.

Like Guerney I have teen daughters too. They are 17, 15 and 12 and I have always been wary of the smartphone and the many forms of social media that exist within them. I'm also wary of anything that allows kids to stay by themselves in their rooms for long periods of time.

Netflix and Stan entered my home on one condition: it does not go on any private devices: no laptops, phones, anything other than the big hulking TV in the lounge room. I have other rules and expectations about smartphones and laptops and the sad thing is out of my family of five I am the one who carries my iPhone around the most and checks it most often.

I don't think I'm a person who is a afraid of change or wants things to go back to the "good ol' days", I'm a person who has learned to listen to that inner, unsettled voice that says something is not right here and you are allowed to do something about it.

It's not over yet, my battle with the smartphone. I need to stay alert, stay informed and keep calm.

I don't think smartphones have destroyed a generation. I think this generation - iGen as they are being called - is pretty wonderful. Much more than wonderful. But I do want to protect them. Scratch that, I want to teach them to protect themselves from any danger they may face, even if that danger has pretty lights and pictures on it, connects me to them and fits perfectly in their lovely soft hands.

It's an instinct.