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

Learn more »

Blog Posts

OpenPGP Considerations, Part III: Autocrypt and Encryption by Default

This blog post is the third in my series on design decisions made in the OpenPGP support in K-9 Mail. Following my first post on signed-only mails, and the second one on encrypted-only mails. This one focuses on Autocrypt, and in particular “encryption by default”.

5.4 Release

After a lengthy merge window the K-9 maintainers are pleased to be able to report that the 5.4 branch has been released.

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!

View archived posts


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.

More »


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

More »


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!

More »