Thunderbird
Thunderbird is a free, open-source email app for Windows, macOS and Linux that also includes calendars and contacts, with an Android app for email. It suits people who want to manage their email and calendars in one desktop program without relying on a big tech company.
Description written from the project's own page; checked by AI.
Screenshots2
From Thunderbird's own page. Click one to see it full size.
Listed in2
The jobs it does, and the closed apps it replaces
Calendar & scheduling
Replaces partlyInstead of Google Calendar, Calendly, Outlook Calendar, Doodle · Desktop only; no phone calendar app
Instead of Gmail, Microsoft Outlook · Desktop and Android apps; no iPhone app
What's missing
Things people miss in Thunderbird. Upvote what matters to you; it helps its team decide.
Facts
Something wrong?
Wrong devices, a wrong description, or it isn't really open source? A mod reviews every suggestion.
What we couldn't confirm4
- Specific open-source license name and terms (no license reported or provided)
- Whether the desktop calendar supports web access, sharing or booking features
- Whether Thunderbird Mobile includes a calendar
- Exact feature set of the contacts component