Thunderbird Beta for Testers

Thunderbird Beta for Testers is a connectivity application developed by F-Droid Open Source, packaged as a single Android APK of version 22.0 weighing in at 31.91 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

1. Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
2. File size is a light 31.91 MB, so it installs quickly even on modest connections.
3. This build is signed by "F-Droid Open Source" — always verify the developer name matches what's listed on the app's official store page before installing an update.
4. After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
5. We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

• Ditch multiple apps and webmail. Use one app, with an optional Unified Inbox, to power through your day.


• Enjoy a privacy-friendly email client that never collects or sells your personal data. We directly connect you to your email provider. That’s it!


• Take your privacy to the next level by using OpenPGP email encryption (PGP/MIME) with the “OpenKeychain” app, to encrypt and decrypt your messages.


• Choose to sync your email instantly, at set intervals, or on-demand. However you want to check your email, it’s up to you!


• Find your important messages using both local and server-side search.

• Thunderbird works with IMAP and POP3 protocols, supporting a wide range of email providers, including Gmail, Outlook, Yahoo Mail, iCloud, and more.

• The trusted name in email for over 20 years - now on Android.


• Thunderbird is fully funded by voluntary contributions from our users. We don’t mine your personal data. You are never the product.


• Made by a team that is as efficiency-minded as you are. We want you to spend minimal time using the app while getting maximum in return.


• With contributors from all over the world, Thunderbird for Android has been translated into more than 20 languages.


• Supported by MZLA Technologies Corporation, a wholly owned subsidiary of the Mozilla Foundation.

• Thunderbird is free and open source, which means its code is available to see, modify, use and share freely. Its license also ensures that it will be free forever. You can think of Thunderbird as a gift from thousands of contributors to you.


• We develop in the open with regular, transparent updates on our blog and mailing lists.


• Our user support is powered by our global community. Find the answers you need, or step into the role of a contributor - whether it’s answering questions, translating the app, or telling your friends and family about Thunderbird.

Is Thunderbird Beta for Testers free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does Thunderbird Beta for Testers require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is Thunderbird Beta for Testers safe to install?
We link to the exact APK published by F-Droid Open Source. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update Thunderbird Beta for Testers?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

1. Tap the Download APK button above and save the file to your device.
2. Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
3. Open the downloaded net.thunderbird.android.beta.apk file from your Downloads folder.
4. Tap Install and wait for Android to finish.
5. Open «Thunderbird Beta for Testers» by F-Droid Open Source and grant only the permissions it actually needs.
6. Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.