In this example, existing polygon features have a Name and Date Changed property.
When the Name is edited, the Date Changed property will automatically update to the current date.
To do that, you need to define a Property Watcher on the Name field with Type=SynchItem.
In the Synch Item Watcher Detail section, you'll notice that there's no provision to specify a dateFormat for the ValueType:
The suggested workaround is to open the XML with a text editor, search for the watchersList tag and edit the valueType from none to dateFormat:
<watchersList><watcher name="UpdateDateChanged" type="SynchItem" alias="Site" operation="" property="DateChanged" redraw="true" valueType="dateFormat" >%Y-%m-%d</watchersList>
Note that this change will not be reflected in the Geospatial Administrator, but will operate fine in the design file:
A sample schema is provided for your learning.