There are so few Windows Phone users compared to Android and Apple that it probably just isn't worth the time and money to port it over.

You're probably right. It'd be like Bethesda making Fallout 4 with Kinect support at this point.

As an aside, the Xbox One's Kinect sounds perfect for a meta-Fallout game. "Buy this game on Xbox One and get exclusive access to 'My Life in the Vault' DR- I mean DLC, where all your actions will be monitored by Micro-I mean the Overseer! *Requires Kinect*"