Paul Graham suspects that we’ll end up calling iPhones, iPads, and their Android equivalents tablets:
The only reason we even consider calling them “mobile devices” is that the iPhone preceded the iPad. If the iPad had come first, we wouldn’t think of the iPhone as a phone; we’d think of it as a tablet small enough to hold up to your ear.
The iPhone isn’t so much a phone as a replacement for a phone. That’s an important distinction, because it’s an early instance of what will become a common pattern. Many if not most of the special-purpose objects around us are going to be replaced by apps running on tablets.
This is already clear in cases like GPSes, music players, and cameras. But I think it will surprise people how many things are going to get replaced. We funded one startup that’s replacing keys. The fact that you can change font sizes easily means the iPad effectively replaces reading glasses. I wouldn’t be surprised if by playing some clever tricks with the accelerometer you could even replace the bathroom scale.
The advantages of doing things in software on a single device are so great that everything that can get turned into software will. So for the next couple years, a good recipe for startups will be to look around you for things that people haven’t realized yet can be made unnecessary by a tablet app.
In 1938 Buckminster Fuller coined the term etherealization to describe the increasing tendency of physical machinery to be replaced by what we would now call software. The reason tablets are going to take over the world is not (just) that Steve Jobs and Co are industrial design wizards, but because they have this force behind them. The iPhone and the iPad have effectively drilled a hole that will allow etherealization to flow into a lot of new areas. No one who has studied the history of technology would want to underestimate the power of that force.