Lee Mallon: “Windows Phone has always been number three in the race and getting slower and slower over time, what Microsoft needs is a seat at the table of the platforms growing at an exponential rate and that is iOS and Android.”
Lee does a really nice job hitting the high points of the acquisition. I think the paragraph above is the real reason. Microsoft needs to be a major player in mobile even if its not on their own OS. They’re already building beautiful, useful, mobile applications for iOS and Android and this acquisition will play to their strength in the enterprise. Who knows if they use Xamarin tools internally, that doesn’t matter. What does matter is they now have a way to give millions of .Net developers the tools they need to succeed on mobile. Couple that with Azure and Microsoft could become a dominant player in mobile development.