I wouldn't call Apple's process of developing the iphone and ipad "starting over" software wise though. As far as I know, the OS of both of these devices is ba

I wouldn't call Apple's process of developing the iphone and ipad "starting over" software wise though. As far as I know, the OS of both of these devices is based on OS X which of course can be traced back to Nextstep. I believe Microsoft did exactly the same thing with win NT; I've seen "embedded" systems running it. I would say what held back Microsoft's mobile devices in the past was UI and usability, which Apple seems to have well under control.