K-9, the robot dog

Advanced Email for Android

K-9 Mail is an open source email client focused on making it easy to chew through large volumes of email

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Blog Posts

Google Summer of Code 2017 Projects

After a couple years break, the K-9 Mail project participates in this year’s Google Summer of Code program. We are taking two students, who will join us in our ongoing effort to make K-9 Mail a modern, fully-featured, and easy to use e-mail client!

OpenPGP Considerations, Part II: Encrypted-Only Mails

This blog post is the second in my series on design decisions made in the OpenPGP support in K-9 Mail. Following my first post on signed-only mails, this one focuses on encrypted-only mails.

User Survey

Help shape the future of K-9 Mail by taking part in a short user survey.

Why APG is no longer supported

With the latest major release from December 2016, K-9 Mail dropped support for APG as an OpenPGP provider. The drop-in replacement is OpenKeychain, which has been actively maintained by Dominik Schürmann and myself since it was originally forked from APG in 2012.

K-9 Mail 5.200 released

After more than 2 years of development time the new version of K-9 Mail now comes with support for email encryption using the PGP/MIME mechanism.

OpenPGP Considerations, Part I: Signed-Only Mails

Background on the decisions taken in our stab at OpenPGP.

K-9 Developer Meet-up

Developer meet-up at c-base.


K-9 Mail has a lot of features and configuration options. Unfortunately, not all of them are self-explanatory, so from time to time you might need to look something up.

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Whether you're looking for help or you want to discuss the latest features, the K-9 community has got you covered.

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K-9 Mail is a community developed project. If you're interested in helping to make the best email client on Android even better, please join us!

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