Epistles Mail vs Mozilla Thunderbird

Epistles Mail is an email app with a unified inbox, offline access, scheduled sending, and calendar tools. It works with Gmail, Microsoft 365, Fastmail, JMAP servers, iCloud, Proton, and IMAP. Mail content, attachments, drafts, and the search index stay on the device, and search runs against a local cache. Its local-first, zero-knowledge encryption model stores ciphertext in Cloud Vault; Epistles servers do not store mailbox content. The app is available on Android, iOS, macOS, Windows, Linux, and the web, as well as Apple Watch and Wear OS. The free plan supports up to two connected accounts. Pro costs $35 per year after a 14-day free trial and allows unlimited connected accounts, with password-protected, expiring email included. Pro uses one flat price rather than per-seat billing. iCloud support includes mail, calendar, and contacts. The watch app supports archive, snooze, pin, template replies, and RSVP. Epistles passed a CASA Tier 2 security assessment by TAC Security.

Mozilla Thunderbird is a free, open-source email application for Windows, Linux, macOS, and Android. Users can manage multiple accounts separately or combine them in a unified inbox. The app includes calendar, contacts, and task tools; desktop users can also work offline and schedule messages. Its interface is customizable, and it supports third-party add-ons. Thunderbird says it does not put ads in the inbox or sell inbox advertising, and that user donations fund the project. It describes privacy and security as priorities and says its open-source code has been reviewed and improved over 20 years. The application is part of MZLA Technologies Corporation, owned by Mozilla.org. Help and getting-started resources are available for desktop and mobile users, with contributors around the world supporting the project. Thunderbird is available free forever, with donations optional; its listed mobile platform is Android.