During fall 2013, Microsoft introduced Remote Desktop clients for iOS and Android, and updated Remote Desktop for Mac OS X. Microsoft is expected to eventually offer Remote Desktop for Windows Phone. Remote Desktop lets users connect to remote Windows PCs.
Last week, Microsoft released Remote Desktop 8.0.5 for Mac OS X on March 12, for iOS on March 15, and for Android on March 16.
See https://www.microsoft.com/licensing/about-licensing/briefs/terminal-services.aspx to learn how to license Remote Desktop Services.