Windows Phone (WP) is a family of discontinued mobile operating systems developed by Microsoft for smartphones as the replacement successor to Windows Mobile and Zune. Windows Phone features a new user interface derived from Metro design language. Unlike Windows Mobile, it is primarily aimed at the consumer market rather than the enterprise market. It was first launched in October 2010 with Windows Phone 7. Windows Phone 8.1 is the latest public release of the operating system, released to manufacturing on April 14, 2014.Windows Phone was succeeded by Windows 10 Mobile in 2015; it emphasizes a larger amount of integration and unification with its PC counterpart—including a new, unified application ecosystem, along with an expansion of its scope to include small-screened tablets.On October 8, 2017, Joe Belfiore announced that work on Windows 10 Mobile was drawing to a close due to lack of market penetration and resultant lack of interest from app developers.In January 2019, Microsoft announced that support for Windows 10 Mobile would end on December 10, 2019, and that Windows 10 Mobile users should migrate to iOS or Android phones.