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Windows 8.1 runs on touchscreen devices as well as traditional computers that rely on a mouse and keyboard. Microsoft designed Windows 8.1 to address widespread complaints about Windows 8. Most notably, Windows 8.1 reinstated the Start button, a familiar navigational feature of previous OS versions. Microsoft also made it easier to open, close and multitask among several apps using a mouse.
Windows 8.1 introduced the Open MDM application programming interface, which allows IT administrators to control and secure devices using third-party mobile device management (MDM) software. The OS also integrated OneDrive (formerly SkyDrive), Microsoft's cloud storage and file-sharing service, with its file system.
Windows 8.1 can run on devices with at least 1 GB of RAM and 16 GB of flash storage -- a lower bar than Windows 8, which required 2 GB of RAM and 32 GB of flash storage.
Microsoft Windows 8.1 was released in October 2013.