Ultimately, Apple has aggregated the best customers, which is why Facebook is trying so hard to wrest control of the ecosystem away from Apple.
That’s why any third party handset offering is doomed to fail. I would like to see Facebook and google wage an all-out ecosystem war with Apple, because I am willing to bet that Facebook and google have more to lose (in terms of money) than Apple (who does have alternatives they can funnel their users towards, such as iMessage, news, browser).
I understand Apple’s intent behind them making their ecosystem so sticky that users stay, which Apple then uses to gain leverage over developers. And I support it in its entirety.