Your Fastmail calendars in Android’s own calendar, so Google Calendar, or any calendar app, shows them and changes them. No Opensolr account needed.
01 · Turn it on
- Open Settings → Mail Accounts.
- Under the account, switch on Calendars in the phone’s calendar.
- Its Fastmail calendars appear in your calendar app, each with its own colour.
Each account has its own switch.
02 · Both ways
- On the phone: an event you add, change or delete in your calendar app goes to Fastmail, with its reminders.
- On Fastmail: changes come to the phone, at least every 30 minutes, and right after you edit on the phone.
- What the phone’s calendar does not show, such as guests and the organizer, is kept as it was on Fastmail.
03 · Turn it off
Switch it off and the calendars leave the phone. Nothing is deleted on Fastmail.