Eventually, all mobile devices will level off with having similar features and form factors, that the only real differentiating value between them will be the variety of apps they support.

So I predict within the next three (3) years, when everyone has a smartphone/tablet of some sort, it won't be the device's hardware features but instead the software available for it, that will make the deciding factor of which to use.

To get that software support you have to win the interests of developers.

And developers go where the money is.