Weight Mate for Windows Phone 7 has just passed certification and is available in the Windows 8 Store for download.
Weight Mate is a great tool is you are looking to track you weight over time.
Weight Mate is Free with Adverts. All Proceeds from this app will be donated to Action Duchenne. You can find out more about Action Duchenne here
You can find Weight Mate for Windows Phone here: http://www.windowsphone.com/en-us/store/app/weight-mate/95ba591b-f7a8-4638-bc58-481c8170d430