Horace Dediu has a fantastic piece on the transition from PCs & Macs to mobile ( link ):

The big change in computing has not been a growing Mac vs. declining PC. It has been a huge surge in mobile device use vs. a decline in PC use overall.

This data is visible in many ways.

[…]

Indeed, because no usurper was allowed to emerge, PC/Windows never moved to a mobile evolution of computing. Microsoft’s platform future was lost because the antibodies which eat disruptions were left unchecked.

But Apple’s immune system was suppressed. It allowed a disruptor to emerge from within. Apple gave birth to its future by suppressing the reaction to that new seemingly parasitic organism. It took an immense willpower to allow this to happen.

But it takes us back to the question of what to do with the incumbent, the donor of DNA and resources. The parent that sacrificed for the child.

[…]

It cannot take on the role of being the future. That belongs to the touch screen devices. It will not morph into a touch device any more than a teen’s parent will become cool by putting on skinny jeans. What it will do is become better at what it is hired to do.

[…]

The Mac is what it is because it’s not alone. It’s part of a family. It is a parent. It strives to be better but will not take the future from its child.
The jobs that require a Mac or PC will continue to shrink & specialize. That’s inevitable, and okay. Bets on the future must keep that front of mind.

Benedict Evans, a few days ago ( link ):

A couple of years ago internet companies moved from having a mobile team and a mobile strategy to what they called ‘mobile first’. Instead of building a product and deciding how and if it would work on mobile, new things are build for mobile by default, and don’t necessarily make their way back to the desktop.

Now, though, I think we can see an evolution beyond ‘mobile first’. What happens if you just forget about the PC altogether? But also, what happens if you forget about featurephones? What happens if you presume all of the sophistication that a modern smartphone has and a PC does not, and if you also presume that, with 650m iPhones in use and 2.5bn smartphones in total, you can build a big company without thinking about the low end anymore?