Sterna Mail
What Sterna Mail is
Sterna Mail is a free, GPLv3 Android email client supporting JMAP and IMAP/SMTP. Multiple accounts can use both protocols together in an offline unified inbox, with local cached mail available without a connection. Reading tools include conversations, search as you type, and snoozing. For composing, the app supports multiple identities with individual signatures, undo send, and scheduled sending, plus calendar tools. OpenPGP encryption is available through an app such as OpenKeychain. Remote images and tracking pixels stay blocked until requested, and tracking parameters can be removed from links. Push notifications can work without Google Play Services through JMAP EventSource, IMAP IDLE, or UnifiedPush. The project says it has no analytics, advertising, crash reporting, third-party SDK, or server receiving project data. Accounts can be configured from an email address or manually. Installation is offered through F-Droid, Obtainium, or direct APK download. Version 1.6.0 requires Android 8.0 or newer.
Who it suits
It suits Android users wanting several mail accounts, offline access, protocol flexibility, and privacy-focused tracking controls. It works with any IMAP/SMTP provider and supports JMAP.
What it does well
- Supports JMAP and IMAP/SMTP
- Offline unified inbox
- Scheduled sending and calendar tools
- Blocks remote images and tracking pixels
- No analytics or advertising
What to know first
- Android platform only
- Version 1.6.0 requires Android 8.0 or newer
- OpenPGP needs an app such as OpenKeychain
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | Free software under the GPLv3. · JMAP support · IMAP/SMTP support · Unified inbox · Offline local cache · Scheduled sending | Free |
| Sterna Mail | Free Android email client · GPLv3 | Free |
As sternamail.org lists them, read 20 Sept 2026. The maker's own page has the final word.
Verdict
Sterna Mail focuses on private, protocol-flexible email for Android, with offline caching and scheduling included. Its GPLv3 licensing and multiple installation routes suit users comfortable with open-source mobile software.
Facts from Sterna Mail's own pages
- App coverage
- mobile · sternamail.org, 20 Sept 2026
- Build verification
- The project says F-Droid rebuilds each release from published source and checks it byte for byte against the distributed app. · sternamail.org, 11 Oct 2026
- Calendar tools
- Yes · sternamail.org, 20 Sept 2026
- Compatibility
- The app works with any IMAP/SMTP provider and supports JMAP. · sternamail.org, 11 Oct 2026
- Encryption
- OpenPGP encryption is available through an app such as OpenKeychain. · sternamail.org, 11 Oct 2026
- Free plan
- Yes · sternamail.org, 20 Sept 2026
- Installation
- The project offers installation through F-Droid, Obtainium, or a direct APK download. · sternamail.org, 11 Oct 2026
- License
- Sterna Mail is free software under GPLv3. · sternamail.org, 11 Oct 2026
- Mail accounts
- It supports multiple accounts, JMAP and IMAP side by side, and an offline unified inbox. · sternamail.org, 11 Oct 2026
- Minimum Android version
- The listed version 1.6.0 requires Android 8.0 or newer. · f-droid.org, 11 Oct 2026
- Notifications
- Push notifications work without Google Play Services through JMAP EventSource, IMAP IDLE, or UnifiedPush. · sternamail.org, 11 Oct 2026
- Offline access
- Yes · sternamail.org, 20 Sept 2026
- Privacy
- The app says it has no analytics, advertising, crash reporting, or third-party SDK, and that the project has no server of its own to receive data. · sternamail.org, 11 Oct 2026
- Product
- Sterna Mail is a private email client for Android that supports JMAP and IMAP/SMTP. · sternamail.org, 11 Oct 2026
- Reading
- Reading features include conversations, search as you type, and snooze. · sternamail.org, 11 Oct 2026
- Scheduled sending
- Yes · sternamail.org, 20 Sept 2026
- Setup
- Users can set up an account using only their email address or enter settings manually if the domain publishes no configuration. · sternamail.org, 11 Oct 2026
- Support
- The project links to an issue tracker for bug reports. · f-droid.org, 11 Oct 2026
- Tracking protection
- Remote images and tracking pixels are blocked until requested, and tracking parameters can be stripped from links. · sternamail.org, 11 Oct 2026
- Unified inbox
- Yes · sternamail.org, 20 Sept 2026
- Writing
- Writing features include multiple identities with individual signatures, undo send, and scheduled send. · sternamail.org, 11 Oct 2026
Where Sterna Mail stands on Freedom251
- Email clients#98 of 142