Otter Mail
Gmail, calm and fast. An app for macOS and Linux, and the same app in your browser at
mail.otterware.app.
- Several mailboxes side by side: Gmail, Outlook and any IMAP server
- Gmail labels, plus saved views that filter across accounts
- A local SQLite cache with full-text search, so mail opens instantly and works offline
- New-mail notifications, and a Dock unread badge
- iPhone alerts for verified Gmail, Outlook and IMAP arrivals, with previews fetched on the phone
- On-device translation of mail in other languages (Apple Translation on the Mac, Chrome's
built-in translator on the web; nothing leaves your device)
- Calendar invitations you can answer in place, and one-click unsubscribe
- An agent that works on your mail through OpenRouter, Claude Code, Codex, Hermes or OpenClaw
- Keyboard shortcuts for everything, editable in Settings
Mac app and web app
Both run the same app and the same mail backend (packages/core); what a browser can't do is
switched off in the web app.
Mac releases support Apple Silicon Macs (arm64).
| Feature | Mac app | Web app in Chrome | Web app in other browsers |
|---|
| Several mailboxes, labels, saved views across them | ✓ | ✓ | ✓ |
| Read, search, compose, drafts, attachments | ✓ | ✓ | ✓ |
| Calendar invitations answered in place, one-click unsubscribe | ✓ | ✓ | ✓ |
| Local cache | ✓ every message, readable offline | ✓ lists and opened messages, in the browser | ✓ lists and opened messages, in the browser |
| New mail in seconds (Gmail push) | ✓ also with the window closed | ✓ while a tab is open | ✓ while a tab is open |
| New-mail notifications | ✓ | ✓ while a tab is open (browser permission) | ✓ while a tab is open (browser permission) |
| Unread badge | Dock | Tab title (and the app badge, where supported) | Tab title (and the app badge, where supported) |
| Otter account: mailboxes on every device, device list | Optional | Required (it keeps the Gmail sign-ins alive) | Required (it keeps the Gmail sign-ins alive) |
| Settings, views, theme, agent settings on every device | With an Otter account | ✓ | ✓ |
| Signatures, kept in Gmail | ✓ | ✓ | ✓ |
| Gmail sign-in | Tokens stay on your Mac | Through our relay (tokens pass, never stored) | Through our relay (tokens pass, never stored) |
| Keyboard shortcuts, edited in Settings | ✓ | ✓ | ✓ |
| Launch at login | ✓ | – | – |
| Default mail app (mailto: links) | ✓ | – | – |
| On-device translation | ✓ Apple Translation | ✓ Chrome's built-in translator | – |
| Agents | OpenRouter, Claude Code, Codex, Hermes, OpenClaw | OpenRouter, Hermes, OpenClaw | OpenRouter, Hermes |
| Drag attachments out to Finder | ✓ | – | – |
| Updates | Automatic | Always the latest | Always the latest |
Install
The native iPhone app supports background notifications after connecting
each mailbox in Settings. Gmail and Outlook request separate limited permissions; IMAP asks
to store its password securely. Message content is fetched directly on the phone for previews.
Download the latest DMG (Mac) or .deb (Debian, Ubuntu: sudo apt install ./Otter-Mail-*.deb)
from Releases.
Installed apps update themselves from the same page. Or open
mail.otterware.app in your browser.
Develop
corepack enable
pnpm install
pnpm dev
See docs/development.md for the full setup and
docs/release.md for how releases are cut. Contributions are welcome;
start with CONTRIBUTING.md.
License
MIT
