K-9 Mail v14.0

Mozilla Thunderbird

• In-app purchases

Download Options

View on Google Play

Screenshots

About this app

K-9 Mail is a 100% open source, privacy focused email client for Android

K-9 Mail is an open source email client that works with basically every email provider.

Features

* supports multiple accounts
* Unified Inbox
* privacy-friendly (no tracking whatsoever, only connects to your email provider)
* automatic background synchronization or push notifications
* local and server-side search
* OpenPGP email encryption (PGP/MIME)

Install the app "OpenKeychain: Easy PGP" to encrypt/decrypt your emails using OpenPGP.

Support

If you're having trouble with K-9 Mail, ask for help in our support forum at https://forum.k9mail.app

Want to help?

K-9 Mail is now part of the Thunderbird family and remains a community developed project. If you're interested in helping to improve the app, please join us! You can find our bug tracker, source code, and wiki at https://github.com/thunderbird/thunderbird-android
We're always happy to welcome new developers, designers, documenters, translators, bug triagers and friends.

In-app purchases

$8.50 - $340.00 per item

Version Information

Version: 14.0
Downloads: 5M+
Updated on: Nov 18, 2025
Released: Dec 13, 2025
Requires: Android 5.0

What's New

- 'Auto-fit messages' setting did not persist
- Edge-to-edge move/copy regressed with 3-button nav
- Swiping message left/right could abort prematurely
- Outlook SMTP failed authentication for some accounts
- Gmail folder prefixes appeared after refreshing folder list
- Quiet time preferences were ignored
- Thunderbird could crash after deleting an account