Musubi vs Tuta Calendar

Musubi is a shared calendar that combines calendars, tasks, and people for everyday planning. Events can appear in multiple calendars, with one update reflected wherever they are shown. It connects with Google Calendar, Apple iCloud, Outlook, Microsoft 365, and compatible CalDAV services including Nextcloud, Fastmail, and Radicale. Synchronization works both ways where provider permissions allow, while read-only calendars remain read-only. Views cover day, week, month, and agenda formats, and personal pages control which calendars and items appear. Tasks sit beside events with status, priority, due dates, and web list or Kanban views. Android and iOS apps provide mobile access; Android adds agenda and month widgets, with reminders scheduled on the device. Musubi is open source under the MIT License and can be self-hosted with Docker Compose v2, a domain, and HTTPS. Hosted Musubi costs nothing during early access. The hosted app and primary database run in Germany.

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.