World'o'Clock is a Windows Phone app that could come in handy if you have to deal with global time zones on a regular basis.
Available for Windows 8 devices as well as our Windows Phones, World'o'Clock will display multiple clocks within the app itself and has the ability to pin individual clocks to your Start Screen. It is not a very complicated app but does a nice job of tracking world times.
Full story from the WindowsCentral blog...