We have just added a new optional widget to the Service Desk section in the dashboard - view incidents by subcategory.
This new widget can be added to your own dashboards by clicking the "Personalize" link on your dashboard screen and choosing "Incidents by Subcategory" - as per the screenshot below:
Once selected, the new widget will be displayed on your dashboard as per the screenshot below:
Clicking on the "pen" icon will allow you to choose which category to map to the widget.
At your service,
The Samanage Team