Revision June 18, 2013
If you elect to use the SkyDrive account as storage this will allow other applications to share and update data.
Enter dates as you weigh. The date is added automatically. If you make a mistake select the record, right click for the app bar and press delete.
Selecting a weight record and invoking the share charm will allow you to share that single weight record with registered applications. For instance I like to tweet my weight when I reach a new goal or personal best.