Fastmail Calendar vs Tuta Calendar

Fastmail Calendar is an online calendar integrated with Fastmail email, available on web, Linux, macOS, Windows, Android and iOS. It supports two-way calendar sync and shared calendars, including business plans with sharing and administrative controls. Users can bring in calendars from Google, iCloud and elsewhere, search instantly, and organize events with drag-and-drop editing. It can show schedules in other time zones, compare emailed event updates with earlier versions, and manage calendars offline in its apps; changes sync when the device is back online. Fastmail documents calendar access through CalDAV and JMAP APIs for account data more broadly. The service is paid, has a 30-day trial and does not list a free plan. Options include Basic at $4 a month, Individual at $6 a month, Standard at $6 a month, Duo at $10 a month, Professional at $10 a month and Family at $14 a month. Longer billing terms have separately listed rates. Fastmail was founded in 1999 and is headquartered in Melbourne, Australia.

Tuta Calendar organizes appointments, business meetings, and repeating tasks across Android, iOS, Linux, macOS, web, and Windows. It supports shared calendars with read-only, read-and-write, or write-and-manage-sharing access. Calendar events, invitations, sharing, and push reminders are described as end-to-end encrypted. Users can send and receive invitations, including password-protected encrypted invitations to external users. Imported calendars sync automatically across devices, while the listed calendar sync type is one-way. Tuta says reminders are hidden from the phone operating system and can arrive offline. The calendar is integrated with Tuta email and contacts. Security features include two-factor authentication; Tuta also describes its clients as open source and its calendar as using zero-knowledge architecture. The Free plan includes one calendar. Revolutionary costs €3 a month, billed monthly, and Legend costs €8 a month, billed monthly; both include unlimited calendars. Tuta is made by Tutao GmbH, based in Hannover, Germany, and founded in 2011.