When looking at the Views - Citrix Virtual Apps and Desktops page of Goliath Performance Monitor, on the Published Apps & Desktops and Virtual Desktops tabs of the display, there is a column labeled Version. The Version column is displaying what version of Citrix Receiver or Workspace app is installed on the end users client machine.
Figure 1 - Published Apps And Desktops tab
Figure 2 - Virtual Desktops tab