Microsoft’s Windows operating system, as we all know, is an OS that powers more than a billion PCs and laptops across the globe. However, as you may know, Microsoft could not keep up the pace in the mobile department, and that, as per Bill Gates, is one of the biggest missed opportunities in his life.

Now, Microsoft, as one might know, did release a Windows-based mobile operating system for smartphones way back in 2010. It was called Windows Phone OS and the company had joined hands with Nokia to develop phones powered by this OS. Microsoft’s Windows Phone OS became the primary operating system for Nokia Lumia devices.

Microsoft later acquired the Lumia brand and continued to release Lumia branded devices with its Windows Phone OS for quite some time. However, as Google’s Android and Apple’s iOS became the primary OSes in the mobile industry, Microsoft terminated the active development of Windows Phone OS back in 2017 and started working on integrations with the said mobile OSes.