Take this for what it’s worth but IDC states that Windows Phone will be world’s 2nd largest OS in 2016 just above iOS but still way below Android. A quick look at the chart also tells me that RIM (aka BlackBerry) will go from 6.0% to 5.9%. My guess is that in four years RIM will not even be a company anymore.
I also think that Apple will lose more market share than this chart would indicate. If all rumors about the new iPhone are true Apple is done innovating in the smartphone market and Apple will just be living off of reputation rather than product. The iPhone is no longer the “phone to have” among tech geeks it’s only a matter of time till that knowledge spreads to the general public.