Microsoft is $4g from its years in the wilderness. One of the biggest problems during that time was the rise of the iPhone and Android in 2008 and 2009, which seemed to catch Microsoft totally off guard.
It's been playing catchup ever since, with no luck. As this chart from $4 shows, Microsoft's mobile market share has been hovering around 3% ever since the release of Windows Phone 7 - the replacement for the old Windows Mobile platform, which was once one of the top three mobile operating systems (along with Nokia's Symbian and BlackBerry's platform).
Although $4 was solid, mobile remains a weak spot - Microsoft's revenue from phones declined 54% from a year ago, and it's dramatically cut back the number of models it's making following the $4 of its acquisition of Nokia.
Statista