To make this pig fly..
you need to vary the form factors. And, dare I say it, lose the Holy Jobsian dedication to the touchscreen as the single form of input.
A smartphone is best outside of office environments. In an office, you have a better option available for everything a smartphone can do, with the single exception of texting and phone calls and for calls, a landline has far less reception issues.
This means the optimum smartphone buyer is actually not the office bound IT wonk (95% android) or Starbucks-dwelling hipster (100% iOS). It's people who work for a living.
A builder wants at the very minimum a hardware "answer call" button so that he doesn't have to get his cement covered thumb on the touchscreen. The lack of one is a hideous oversight. Ideally he wants a clamshell phone which protects the screen.
He'd like big buttons because he is not a girl (usually) with tiny fingers and therefore T9/predictive and numeric buttons are optimum. If he could flip a slider and manage all the touchscreen magic from the keypad, he'd probably be delighted. He is outdoors so the screen must be matt. He wants bluetooth because he doesn't want a fine for answering calls in his van.
He'd probably like big or replaceable storage for music but I doubt he's ever going to be using this as a portable video player. He needs email and CAD-produced images delivered promptly and he'd like to be able to return his comments.
Basically, the current crop of smartphones are toys. Expensive toys but still toys. This market is underdeveloped until phones that do work environments start appearing. When that happens, whichever OS can handle it will be the one that takes the spoils.
As of right now, that's none of them.