This app was mentioned in 9 comments, with an average of 2.11 upvotes
I've managed to do it with the "offline calendar" app (which is foss).
You can find it on: Play store: https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar
F-droid: https://f-droid.org/app/org.sufficientlysecure.localcalendar
Damn, you just beat me to it! Sufficiently Secure's offline calendar will do just the job:
https://f-droid.org/app/org.sufficientlysecure.localcalendar
https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar
Did you find anything out? This bothers me too.
edit: I installed https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar and their other app https://play.google.com/store/apps/details?id=org.birthdayadapter.free and it seems to do what I need.
Use https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar to create a local calendar, then you can just use https://play.google.com/store/apps/details?id=com.google.android.calendar to add events to it and to another shared calendar.
> Use https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar to create a local calendar, then
Offline calendar seems to just let me create a calendar title and set a color to it, other than that I can do nothing else. All the other calendar apps on my tablet pick up on those offline calendars and pull them in. So I don't get the point. The other apps seem to have a "local" option. But it seems accessible to everything on my phone. The only one that doesn't do this is jorte I think.
>You can just use https://play.google.com/store/apps/details?id=com.google.android.calendar to add events to it and to another shared calendar.
Not google.
What you're looking for is this. Its an app (not a calendar app) that simply creates offline calendars that other calendar apps can see and use. So you can choose any calendar app you want, and then use this app to create an offline calendar that your calendar app can use.
Offline Calendar https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar
If I understand your request, offline calendar is what I use. https://play.google.com/store/apps/details?id=org.sufficientlysecure.localcalendar