K-9 Mail

Name: K-9 Mail
Availability: InStock
Rating: 3.5799999237060547 (99995 reviews)
Author: Mozilla Thunderbird

Mozilla Thunderbird

In-app purchases

3.6

100K reviews

5M+

Downloads

PEGI 3

About this app

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.

Updated on

3 Sept 2025

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region and age. The developer provided this information and may update it over time.

No data shared with third parties

Learn more about how developers declare sharing

No data collected

Learn more about how developers declare collection

Data is encrypted in transit

Data can’t be deleted

Ratings and reviews

3.6

94.8K reviews

Jared Reid

18 July 2025

the app is okay, though I'm not a fan of the way the unified inbox is sorted, like it isn't the top heading in a folder with multiple inboxes. it's not intuitive. and, what about unified spam, trash, and draft folders? good UI and it works well enough without ads on your face.

12 people found this review helpful

Mozilla Thunderbird

18 July 2025

Thanks for your review! We're responding to feedback like yours, and our upcoming changes to the account drawer will also include a better experience for the Unified Inbox and other unified folders. You can read more and see screenshots in the Juny Mobile Progress Report at blog.thunderbird.net!

LNX

11 September 2025

It takes a bit of getting used to, but overall it works well. One major minus is that there is no option to print an email (or create a pdf). Why is something so basic not included?? The lack of print/pdf functions removes 2 stars! If ever there was something to improve on, this is it. I am still in shock. I don't want to have to email myself to a different email address on a different app to print an email. Please sort this out asap.

Mozilla Thunderbird

19 September 2025

We're so sorry for any frustration! K-9 Mail doesn't have a built in ability to print emails yet. While we don't have a date for when it will be added, we use feedback from reviews and connect.mozilla.org to help shape our roadmap and prioritize new feature development!

Sara Gartner

17 July 2025

Professional design, aliases supported, missing signature formatting though I was looking for an Android alternative to Outlook as it does not support email aliases. So grateful that K-9 Mail does. I was worried about the design and functionalities, but these are well carried out. One star less though for the missing signature formatting. I'd need to format the text and add an image for business emails. Hoping for that feature to be added soon! 🙏

8 people found this review helpful