Calendars over CalDAV

A calendar app signs in with the same username and app password as a mail app, and reaches the calendar of that one address.

• —Calendar apps find the rest by themselves: /.well-known/caldav sends them to /dav/, and from there to the calendars of the address.
• —Seeing the calendar needs permission to read it, and changing events needs permission to change it.
• —A password made through a setup link opens the calendar as well as the mail, but never the contacts.
• —The calendar can be switched off for one address with its CalDAV switch, in the Servers view of the Mail apps tab.
• —Contacts sync the same way over CardDAV, with the same server, username and password.

1. 1Open Settings, then Apps, then Calendar, then Calendar Accounts.
2. 2Tap Add Account, then Other, then Add CalDAV Account.
3. 3Enter api.openemail.uk as Server, the whole address as User Name, the app password as Password and a Description such as Work. Tap Next.
4. 4Leave Calendars on, turn Reminders off, and tap Save.

• —The profile from the Mail apps tab adds the calendar and Mail together, in one step.
• —OpenEmail keeps events only, so reminders stay on the device.

1. 1Open Calendar and choose Calendar, then Add Account.
2. 2Choose Other CalDAV Account, then Continue.
3. 3Set Account Type to Manual, enter the whole address as User Name, the app password as Password and api.openemail.uk as Server Address, and choose Sign In.

1. 1Open the Calendar tab and choose New Calendar.
2. 2Choose On the Network, then Next.
3. 3Enter the whole address as Username and https://api.openemail.uk/dav/ as Location, and choose Find Calendars.
4. 4Sign in with the app password when asked. Thunderbird lists the calendars of the address. Tick the ones you want and choose Subscribe.

1. 1Install DAVx5 from Google Play or F-Droid and open it.
2. 2Tap the plus button and choose Login with URL and user name.
3. 3Enter https://api.openemail.uk/dav/ as Base URL, the whole address as User name and the app password as Password, then tap Login.
4. 4Keep the whole address as the account name, which DAVx5 uses as the organiser of events you create, and tap Create account.
5. 5Open the CalDAV tab of the new account and tick the calendars to sync. They then show in Google Calendar and every other calendar app on the phone.

• —A calendar app signed in as an address sees the events that address organises or is invited to, and the events you created yourself. Your subscriptions show beside them as read-only calendars.
• —The calendar is called OpenEmail in the app. Each subscription keeps the name you gave it, and renaming one in the app renames it in OpenEmail.
• —Events from about three years ago to ten years ahead stay in step. Older and later ones stay in OpenEmail.
• —An event can be up to 1 MB. Tasks and reminders are not kept.
• —Apps that look up when people are free can see when other addresses of the workspace are busy, up to 120 days at a time.

• —Inviting people from the calendar app sends real invitations from that address, and answering an invitation there tells the organiser, as the buttons in OpenEmail do. Changing events needs permission to change the calendar, and sending invitations needs permission to send from the address.
• —Changing the time, place or details of an event you organised sends the guests an update, and removing a guest sends that guest a cancellation.
• —Deleting an event you organised with guests cancels it for all of them. Deleting an invitation you received declines it.

Google Calendar and Outlook.com cannot sign in to another calendar server, so give them a calendar link instead.

• —The app keeps asking for the password: the username must be the whole address and the password an app password for it. OpenEmail answers such a sign-in with Sign in with your email address and an app password from OpenEmail.
• —The app signs in but finds no calendar: check that the server is api.openemail.uk, not the domain of the address, or enter the full address https://api.openemail.uk/dav/.
• —This kind of connection is turned off for this address: the CalDAV switch of the address is off. Ask the workspace owner, or someone who manages domains, to turn it on.
• —Events cannot be changed: the person whose password it is may only read the calendar, or the event belongs to a subscription.
• —Revoking the app password signs the calendar app out within about five minutes.