This week, Intel CEO Brian Krzanich announced that people are keeping their PCs a lot longer before upgrading: The average has increased from four years to as many as six.
The tablet-refresh cycle isn't much shorter than that, to Apple's eternal chagrin. Even iPhone sales have started to taper off, partly because people are keeping their phones longer or choosing cheaper Android phones.
What's happening is pretty simple. The hardware and the software running on any device itself have become way less interesting than the web apps and services, like the ones that Google and Amazon have made the core of their business.
Why buy a $700 iPhone when a $200 Android phone can access the same YouTube or Amazon Music as everyone else? All you need to do to get new Facebook features is refresh your browser or update your app. You don't need a high-performance device to participate in the 21st century.
It's a stark contrast with the traditional model for consumer electronics, where you're expected to upgrade the hardware to keep pace with the new features they release.