The game is about to change again. The device isn't going to be as important was what is behind the device and the Human Machine Interface. Everyone knows this which is why the valley is pushing into machine learning, autonomous system, big data, and thinking/learning machines. This is where the next trillion will come from unless someone can engineer a phone that thought controlled.
Other big money areas are battery technology. Imagine if Apple could put out a smartphone with a patented battery technology that lasted 1 month between chargers, that would be a game changer and everyone would flock to it. Material science, vehicle engineering, and embedded medical devices will also be other larger growth areas.
We now have the power, silicon, and networks for some amazing technology to blossom, but it is handwork and will take dedicated teams working together over many years. Google, Apple, Microsoft, IBM, and even Amazon all have a shot at making this a reality. Anyone can make a flat thin square with a touch screen and voice recognition that talks to a cloud backend. Now it is time to see how far we can go with this new platform and how it can benefit humanity or at least make money.