Windows Phone 7

Windows Phone 7 was the sixth installment in the Windows Mobile line. Windows Phone 7 was the first Microsoft developed mobile operating system to be designed for touchscreen smartphones with the rise of iOS and Android. Windows Phone 7 was also the first Microsoft OS to have the Metro user interface that would eventually make its way onto desktops in Windows 8. Windows Phone 7 added the Windows Store a marketplace for apps to compete with Apple's App Store and the Google Play Store.