Why Microsoft needs to unify the many faces of Cortana

Microsoft has waxed and waned in the past between a single, unified UI design for its apps and services to more tailored ones that better fit into specific platforms. This shift in design philosophy was expressed profoundly in Skype, which for many years looked like the PC desktop version, then shifted countless times with various changes in design. To be fair, the approach of tailoring something like Cortana for Android is welcome. While Microsoft idealists believe the company should turn Android into a pseudo-Windows Phone with Live tiles, cooler heads have prevailed. Instead, Microsoft's apps for Android embrace Google's design choices to blend in better.