Many times we use various apps/websites in combination to do our tasks. Or we use multiple gaming/entertainment apps. Allowing the users to define categories and add specific apps/websites into those categories could give a better understanding of out time breakdown throughout the day.
For example, I use Unity game engine, Visual Studio and Blender in connection to each other during my work day. Combining these into a "development" category would allow me to see how much time a day I spend on "development". Or I can group Steam, Epic, and my installed games as a "Gaming" category and see how much time I spend gaming in a day.
