A strong argument is that software developers, especially the big ones, do not want to have multiple products. Since everyone on the planet seems destined for a smartphone, the user interface for mobile devices will be the standard in the very near future. Never mind that it isn't particularly productive for someone with multiple displays and separate keyboard and mouse.
Electronic manufacturers are generally going to build what customers are purchasing and that appears to be products like tablets. Yet even sitting in front of the television, I prefer a laptop to tablet. When I type, I want to be efficient - I don't like the inefficiency of touchscreen keyboards. A good friend of mine declares "tablets are great for an internet snack".
I think he is right. The mobile devices allow seamless communication, but they are asymmetrical - they are terrific at consuming information, but not producing content. That gives me pause. Has our culture changed to where we no longer desire to be inventive or productive? Do we just want to consume content and never create it ourselves?
Science fiction aficiondos remember this was a theme in Isaac Asimov's Foundation trilogy. The empire began declining when its population ceased to be inventive or productive, essentially consumers of content. Has more changed than just the computing devices we use? Which happened first? The iPhone/iPad or the shift to content consumers?