Slugs to be you then, I guess. :P
In all seriousness, the graph shows different species as fraction of total uses recorded. Since the paper is mostly about mice, and behavioural differences under different circumstances, it being unfair to the slugs is probably not such a big deal here.
I hate the fact that none of the big names support CalDAV natively. DAVx5 is cool and all, but app developers really need to step up their shit and support CalDAV already. Not just Microsoft Exchange and Google Calendar but CalDAV as well. It’s not like they need to rebuild their apps from scratch.
At this point you might just be better served using a web app instead of a native mobile app. Maybe K-9 Mail transformation into Thunderbird Mobile might bring some good news, but I’m not holding high hopes.
Maybe we should, under the EU’s DMA, force anyone that bundles a calendar/note app with their phone OS to support CalDAV as well as any proprietary protocol of their choice.