Marc Kalmes 
Inspired by @moonglum, I've moved two calendars from iCloud to another CalDav server. #DidIT
Feb 4 at 4:07pmWeb
Show threadLucas DohmenFeb 4
@mkalmes Awesome ❤️ Great work!
Show threadWhiteHotaruFeb 4
@mkalmes @moonglum do you two have any tips on shared calendars for a family, which are editable by multiple parties?
Show threadLucas DohmenFeb 4
@whitehotaru @mkalmes From what I know, there is no way to have a calendar shared between two calendar services (any two!) and make it editable for all. The only solution I know are subscriptions and that means part of the group can‘t edit 🙈 I think this is a severe problem in the iCal standard. You can only have a mutable shared calendar if everyone uses the same service.
Show threadMarc Kalmes Feb 4
@whitehotaru @moonglum
Sadly no. That’s the reason I keep some calendars in iCloud.
If I remember correctly, @Tutanota has that option, but I’m not 100% sure.
Show threadTutaFeb 5
@mkalmes @whitehotaru @moonglum Yes, if all users have a paid plan, they can share their calendars in Tuta Calendar.
Show threadLucas DohmenFeb 5
@Tutanota @mkalmes @whitehotaru They can share a calendar with people using iCloud, and everyone can write to the calendar?
Show threadNilsFeb 5
@moonglum @Tutanota @mkalmes @whitehotaru I don‘t think so, at least that was one reason I‘ve selected Fastmail for the family. Still like Tuta very very much for secure mail, great product!
Show threadTutaFeb 5
@derMerl @moonglum @mkalmes @whitehotaru Sharing to iCloud is not possible due to the encryption. Sharing of entire calendars only works with other Tuta users. But we're planning to also add a feature to share calendars outside of Tuta.
Show threadWhiteHotaruFeb 5
@moonglum @Tutanota @mkalmes we are fine with Accounts at one provider. At the moment our accounts are at Posteo.de and even if both accounts are at Posteo, you can only share read only.
Show threadLucas DohmenFeb 5
@whitehotaru @Tutanota @mkalmes oh, okay, having mutable calendars shared with people on the same service is a baseline feature almost every provider has. We use Mailbox.org, and have multiple shared writable calendars.
Show threadWhiteHotaruFeb 5
@moonglum @Tutanota @mkalmes Thanks. I’ll look into this. I’ll ask Posteo, if they could make it happen, as we are happy in general with the provider. By the way: if you are looking into a simple shared calendar, which is writable without an account, I can recommend Feber (https://simonrepp.com/feber/). I use it for a shared Garden-Project.
Feber

Feber is a simple, self-hostable group calendar