Now that Windows 10 for PCs and tablets is out the door, it's only natural to think of the next big launch. Apparently, that's also the same line thinking going on inside the Windows Team's head. After focusing all their resources on PCs and tablets, they are now refocusing on the smartphone. After a bit of a hiatus, Microsoft is rolling out Build 10512 for Insider Preview on the fast track. Though a mix of improvements and issues, the build assures fans that Windows 10 is inching slowly to Mobile.