Unlike Apple, which thinks merging iOS and OS X would be a “waste of energy,” Microsoft wants one single Windows operating system to be available to all its device users, whether they’re Windows Phone handset owners, Xbox fans, or rely on a Windows computer for work or play. Business Insider reports that CEO Satya Nadella said on the company’s FQ4 earnings conference call that a future version of Windows will merge all current Windows versions, becoming an “operating system that covers all screen sizes.” “In the year ahead, we are investing in ways that will ensure our device OS and first party hardware aligned to our core,” Nadella said. “We will streamline the next version of Windows from three operating systems