“Are you playing a game?” I looked up to find a boy of about 6 years old, in his school uniform and still wearing his rucksack, reaching out towards my iPad. His sister, a year or two younger, looked on with equal curiosity. I’d been absorbed in my work, balancing the iPad on my knees and tuning out the mayhem of the early evening commuter train on the last Friday before Christmas.

The MEX series of user stories has focused so far on situations where I could be a passive, unnoticed observer – but one of the vagaries of user research is that you cannot choose the moments when the line between researcher and participant becomes blurred.

Despite my best efforts to ignore the hustle and bustle of my fellow passengers, it was hard not to notice these particular kids. They were everywhere and seemingly oblivious to the grumbles of the adults around them. Their mother, her eyes mainly on a third, even younger daughter, seemed resigned to the limitations of her power and was pursuing a strategy which combined both 1930s-style appeasement and a late 20th century blend of sanctions and threat of force.

I instinctively tilted the iPad away from the little hand reaching towards it, but it was interesting how natural this was for the young fellow. Tablets, it seemed, were fair game in his world – even when they belonged to strangers on a busy train.

I had to disappointment him. “No, sorry, not a game,” I replied truthfully, looking down at the page of typed text which was anything but playful.

“Have you got *any* games on there?” He wasn’t to be easily deterred it seemed.

“No, just work,” I replied. I had no intention of letting this little monster get his paws on my iPad.

I had, of course, underestimated how observant kids can be, especially when they sense something to their advantage. “What about on there?” He started to move toward my iPhone, wrapped in a case, which was sitting on the little table below the window and serving as a hotspot for my iPad.

His tone suggested he had made a winning discovery: in his mind, there was no possibility that I wouldn’t have games on at least one out of my two gadgets.

“Nope,” I told him, but I’m not sure he believed me. I suspect he has heard this type of reply from adults before, only to find that their iPads and iPhones did, indeed, hold a treasure trove of games if only he was persistent enough in his interrogation.

His sister had now seated herself next to me and saw her opportunity to open a new front of attack.

“Isn’t that mooring?” She asked, struggling a bit with her diction.

“Um, sorry, say that again…”

“Isn’t that boring?” She clarified, a bit louder this time.

“It can be,” I said. It was hard to argue with such insight. “But just got some work to do,” I continued, forgetting that at age 5 and 6 they probably lacked the ability to perceive a nuanced hint this conversation was at an end.

“Yeah, games can cost money, can’t they,” the boy told me. At age 6, it seemed, he was already conscious games came with consequences.

However, then he really surprised me.

“Some of them are free downloads…but then they end up costing you!” He sounded indignant and emphasised the end of his statement, as if to stress just how much pocket money was at stake here.

“You’re not playing with that man’s tablet! Stop bothering him!” Mum had decided to step in and the kids, reluctantly, sat back in their seat as she offered a distracted: “Sorry…” Then she turned back to see what was happening with her third charge.

It caught my attention she’d called it a ‘tablet’. Did that suggest that in their household they used something outside of the iOS ecosystem? The majority of users in the UK still default to ‘iPad’ as the generic term for tablets of all brands. Maybe the arrival of low cost tablets like Tesco’s Android-based Hudl and sub-£100 Windows devices in family shopping destinations like the big supermarkets is starting to change perceptions.

There was a pre-Christmas offer in the UK which, when combined with a supermarket loyalty scheme, brought the effective price of an entry-level Window 8.1 tablet down to about £30. To put that in perspective, that’s about half what you’ll pay for the little scrap of plastic Apple calls the ‘official’ iPad case – if you want a functioning tablet to go inside it, you’ll be paying at least ten times more. If you ever needed evidence Microsoft is prepared to start a price war to maintain market share…

I (and I suspect most other readers of this journal) might be lucky to have the privileged luxury of using the latest iPads, iPhones and Android flagships by virtue of our jobs in the industry, but as I sat there on the train that evening, the scene playing out in front of me painted a very different picture. This was an image of a far larger swathe of the market, where the falling cost of mobile computing is beginning to affect households who wouldn’t ever plan to spend the £500 – £1000 price tags demanded at the high end, but are now starting to migrate at much more accessible prices.

This movement feels like the point at which the last vestiges of tethered computing in the home – desktop PCs and, to a lesser extent, consoles – start to fade in significance. They will remain, of course, for certain niches, but the attitudes of kids like those I encountered on the train show how quickly the ubiquity of mobile computing has become the norm.

With this acceptance is coming a new vocabulary about ‘app stores’, ‘in app purchases’ and ‘fremium games’, which is the natural consequence of people buying – often speculatively – these cheap mobile computers with their easy access to downloads and new ways of spending money. What does it say, when, at age 6, this boy already had a nuanced enough understanding of the hidden costs of downloading games to be explaining it to me – a complete stranger – on the train?