The complaint in both cases was that of course smartphone sales are bigger than PCs, but that's unfair - the phone market is just much bigger than the PC market (and the devices are replaced every ~2 years where PCs are replaced every ~5 years). Plus, it's unfair to compare PCs with mobile devices because some of the things you do on PCs are hard to do on mobile devices (at least for now).

These objections were quite correct - the comparison is unfair. But it's also relevant. Mobile is now around half of all time spent online in developed markets and will be the dominant global consumer computing platform of the next decade or two. And the sheer scale of the smartphone businesses is driving a reshaping of all the dynamics of the technology industry, while its supply chain is enabling all sorts of new segments that would never have been possible before - drones, wearables, VR, micro-satellites, internet-of-things devices and lots of other things besides.

Hence, another deeply unfair but deeply relevant chart: Microsoft's share of the sum of all personal computing devices: Windows PCs, Macs, iOS and Android devices and Windows Phones (I could arguably include games consoles in here - my inclination is not to, but it wouldn't change the chart noticeably).