Matt thinks out loud about the smaller screen size of the iPad Mini, and the growing screen size of many smartphones:

“On the smartphone side, people are caring less about making phone calls and more about being able to access their digital world regardless of where they are and what primary activity they’re engaged in. Smartphones and tablets both do that last bit well, but a larger screen is needed to gain higher utility. This is “relationship-centric” computing, the hallmark of what makes a post-PC device.

The problem with smartphones is that people want them with them all of the time, but only half of these people (typically women) use purses. (“Handbags” if you prefer the British vernacular.) If you’re an individual who happens not to routinely use a purse, the most practical way to tote something around is in your pocket. Hence smartphone want to be bigger to gain utility, but sizes are capped by the typical carrying capacity of a man’s pocket.

I’m not entirely convinced however that in this instance people want to have two devices because both smartphones and tablets do the same basic job of relationship-centric computing. If I happened to routinely carry a purse, an optimum arrangement for me would be to carry around a tablet and have a feature phone for making emergency phone calls. Plus, if I’m carrying around a tablet in a purse, I’d rather it was a small 8″ device than a larger 10″ device especially if there was no standout reason why the extra screen size was an absolute requirement. If everyone in the world carried a purse every time they left the house, perhaps we’d be looking at smartphones and tablets both ending up around the 8″ size.“

Read more: Has Apple redefined the tablet as an 8″ device?