XAML Spy Express is the free edition of XAML Spy. XAML Spy Express provides a limited, but useful set of features that allow you to spy on XAML apps for free. See the comparison chart below for more details on the features that are available in the Express edition compared to the licensed editions.
When installing XAML Spy for the first time, you can evaluate the product for a limited period. During the evaluation period you have access to all features of XAML Spy. Once the evaluation period has expired, XAML Spy will automatically switch to the XAML Spy Express edition, unless you purchase a license.