I use Apple’s Notes, Reminders, Calendar app and Safari and I would like to beemind them. “Fewer than n items in Reminder list xyz”, number of items on your reading list (= firefox pocket) and so on.
I see two options here: Integrate with iCloud (no idea how feasible this is) or have a script run on your mac that queries these apps locally and syncs to Beeminder (fairly easy to do (I reckon), but less reliable, but probably reliable enough. Also allows for loopholes by terminating and messing with that script.).