Thunderbird

Google Calendar

1. Install Addon Provider for Google Calendar
2. In the Calendar Tab click on New Calendar Google Calendar and add your google account.

CalDav

1. In the Calendar Tab click on New Calendar On the network
2. Enter your username and the caldav address

Android

Google Calendar does not support synchronizing caldav calendars. Instead, a synchronisation app is required.

DavX⁵

DavX⁵ is an open source app that syncs external calendars with android calendar storage. Free to install on Android via F-Droid, paid in PlayStore.

• Give all required permissions to the app (the app will request this by default)
• Add the google account by granting the app permissions to your calendar.
• Add the caldav calendar

Etar

Open source Calendar app. Etar on GitHub

Once granted permissions, the app should immediately contain all calendars synced in the android calendar storage.