The open source Thunderbird email client has a long and storied history, but until now, that history has been limited to the desktop. That's about to change, according to a post on the Thunderbird blog. Thunderbird will be coming to Android through the popular open source mobile email client K-9 Mail.

According to Thunderbird's Jason Evangelho, the Thunderbird team has acquired the source code and naming rights to K-9 Mail. K-9 Mail project maintainer Christian Ketterer (who goes by "cketti" in the OSS community) will join the Thunderbird team, and over time, K-9 Mail will become Thunderbird for Android.

Thunderbird's team will invest finance and development time in K-9 to add several features and quality-of-life enhancements before that happens, though. The blog post lists these bullets on the features road map:

Account setup using Thunderbird account auto-configuration

Improved folder management

Support for message filters

Syncing between desktop and mobile Thunderbird

Once certain development milestones are reached, and K-9 Mail has been satisfactorily brought "into alignment with Thunderbird's feature set and visual appearance," K-9 Mail will be rebranded as Thunderbird. The blog post doesn't identify a specific timeline for this transition.

A FAQ on the Thunderbird website answers some questions about which features may be included in the mobile app, why the team decided against building a new app from scratch, and so on.