no installation necessary

With this miniaturization of OS's by Apple, Microsoft , and Google, I wonder if we are on track to see the development of computers, cell phones, maybe even gaming consoles merging into a terminal/client relationship, in which the the entire ecosystem of applications for a tiered organization is streamed and tied together? For example, due to hard drive maximization, all of Apple's apps are server-based, and could be streamed to your macbook, your iphone, or whatever other peripherals that they may develop? Would this evolve into pay per use or subscription apps, and a new model of sustained revenue for lesser used but useful software applications? Is it possible by Google, since they do not have a hardware tier?

iTunes, but for software...?