Epistles Mail vs Mailspring

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.

Mailspring is a desktop email client for Linux, macOS, and Windows, with support for multiple accounts in one inbox. It connects to Gmail, iCloud, Office 365, Fastmail, Outlook.com, Yahoo!, and IMAP/SMTP providers, and indexes email for advanced Gmail-style searches across connected accounts. The client works offline and supports scheduled sending. Its free features include undo send, spell and grammar checking, custom themes, dark mode, and localization. Pro adds read receipts, link tracking, send later, follow-up reminders, templates, contact profiles, snoozing, and mailbox insights. Mailspring connects to mail providers through IMAP and to calendars and contacts through CalDAV and CardDAV, though calendar tools are not included in the app. It can translate drafts into Spanish, Russian, simplified Chinese, French, and German, and offer to translate incoming messages. Mailspring says credentials are kept in the system keychain and email is not processed in the cloud. The free plan is available; Pro costs $8 a month, billed monthly.