Microsoft (NASDAQ: MSFT) is in the process of rolling out its latest smartphone operating system, Windows Phone 8.1, and reviewers have been almost universally positive of the latest version of the platform. Importantly, Windows Phone 8.1 stands up well against its larger rivals, Apple's iOS and Google's Android, according to the reviews.
Moreover, Windows Phone 8.1 represents the culmination of a significant push within Microsoft to overhaul and unify its smartphone platform. Microsoft replaced its aging Windows Mobile operating system in 2010 with Windows Phone 7, and then with Windows Phone 8 the company moved from the Windows CE kernel to the Windows NT kernel, thus more closely aligning its smartphone operating system with its desktop operating system. Now, with Windows Phone 8.1, Microsoft has fleshed out and improved the operating system for users.
Notable updates in the Windows Phone 8.1 upgrade include Cortana, Microsoft's voice-activated personal digital assistant, as well as improvements to app notifications and Wi-Fi setups.