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Download Thunderbird Beta for Testers (f-droid version) APK 11.0 arm64-v8a, armeabi-v7a, x86, x86_64 · Android 21+

By Mozilla Thunderbird • Updated June 28, 2026
Communication arm64-v8a, armeabi-v7a, x86, x86_64 Native (Java/Kotlin) 11.43 MB
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This is the arm64-v8a, armeabi-v7a, x86, x86_64 build of Thunderbird Beta for Testers (f-droid version) 11.0. Pick this build if your device's primary ABI matches.

File size: 11.4 MB   •   Min Android: 21   •   Target Android: 34   •   Version code: 39025   •   Framework: Native (Java/Kotlin)   •   Permissions: 16

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File Information

Package Namecom.fsck.k9
Version Name11.0
Version Code39025
Architecturearm64-v8a, armeabi-v7a, x86, x86_64
Min Android VersionAndroid 21 (API 34)
Main Activitycom.fsck.k9.activity.MessageList
FrameworkNative (Java/Kotlin)
File Size11.43 MB
Signature (SHA1)A8240C05184D797C87EFED01D907961F8B4AD62B
File Hash (SHA256)0f2c3f346819f47edf4cad2cbaae6ae0c438a6f2d2c6e91cadb3c7b00ee554b0

What's New

New in version 11.0
- Improved drawer navigation
- Improve dark mode emails
- Welcome screen layout improved
- Improved compatibility with some ISPs
- Selection now shown by adjusting color priority
- Folder settings now use switches instead of checkboxes
- Messages now marked read by default when archiving
- Font size config preference removed in favor of OS and density settings
- Avoid crashes in various scenarios

App Description

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

.

Want to help?

K-9 Mail is 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.

License:

Apache License 2.0

Website

Issue Tracker

Translation

Source Code

Changelog

Build Metadata

Reproducibility Status

APK Permissions 16

  • android.permission.ACCESS_NETWORK_STATE
  • android.permission.CAMERA
  • android.permission.FOREGROUND_SERVICE
  • android.permission.FOREGROUND_SERVICE_DATA_SYNC
  • android.permission.FOREGROUND_SERVICE_SPECIAL_USE
  • android.permission.INTERNET
  • android.permission.POST_NOTIFICATIONS
  • android.permission.READ_CONTACTS
  • android.permission.READ_SYNC_SETTINGS
  • android.permission.RECEIVE_BOOT_COMPLETED
  • android.permission.SCHEDULE_EXACT_ALARM
  • android.permission.USE_BIOMETRIC
  • android.permission.USE_FINGERPRINT
  • android.permission.VIBRATE
  • android.permission.WAKE_LOCK
  • com.fsck.k9.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

Frequently Asked Questions about Thunderbird Beta for Testers (f-droid version) APK

This variant is built for devices that report `arm64-v8a, armeabi-v7a, x86, x86_64` as their primary ABI. If your device's CPU matches, this is the smallest, fastest version to install.

Yes — the APK's signature has been cryptographically verified against the publisher's signing key. The SHA-256 hash is shown in the File Information panel so you can independently confirm the file matches the original release.

Android 21 (API level 34) or newer. Older devices will refuse the install.

Install a free app like 'CPU-Z' or 'Droid Hardware Info' from the Play Store and look at the ABI / Instruction Set row. Most phones made after 2017 are arm64-v8a; if in doubt, download the universal variant.

All variants are functionally identical — same features, same version. They differ only in which CPU architectures the native code is compiled for, and (sometimes) which screen densities the included graphics target. Pick the one that matches your device for the smallest install size, or pick 'Universal' if you're unsure.