My only question is now whether page_view_logged_in_mobile is a subset of page_view_logged in, and the same on the anon side. Or do I need to sum the numbers to get totals?
I’m fairly sure that page_view_logged_in and page_view_logged_in_mobile are calculated separately. Assuming that is correct, you will need to sum the two counts. It seems likely that page_view_anon and page_view_anon_mobile function in the same way.
Unfortunately, requests to the app are not saved on Discourse development sites and I don’t have a production site at the moment, so I’m going from memory and a quick look at the code to answer this. Maybe someone else can confirm.