IMHO, when the iPhone came out, it did not introduce almost anything revolutionary over the already available Windows Mobile PDA devices, it only simplified, polished and packaged the device way better. I still do not understand how Microsoft, considering their extensive experience in operating system development, somehow managed to lose their entire, massive mobile device market share in the course of only a couple of years. All it could have taken for Microsoft to win over Apple was to switch Windows Mobile from a cumbersome stylus-based UI to a convenient touch-based UI without wasting years and years to re-develop the misguided Windows Phone from scratch.