I personally believe in the "winner takes it all" story here.
Before apple has launched an iPhone, appStore, iTunes and etc, the world of gadgets was extreamly fragmented and everyone was trying to focus on a niche.
Some have tried to make everyting for everyone an failed. We all know this common critics of "everything for everyone"
However combination of all-in-one platform with the power of third party developers and community is the solution in my opinion.