'K-9 was one of the first third-party email clients on Android, and it developed a large user base among users who had to keep track of multiple inboxes. The feature is expected to be implemented in the summer of 2023.Īndrew Cornwall, a senior analyst with research firm Forrester, called the K-9 Mail annoucement 'significant.'

Mozilla plans to offer Firefox Sync as one option to allow users to securely sync accounts between Thunderbird and K-9. 'In other words, K-9 Mail will soar to greater heights with the help of Thunderbird.” Ryan Lee Sipes, Thunderbird Product Manager, said working with the Thunderbird email team to develop the new mobile client made more sense than developing a mobile client from scratch. “Joining the Thunderbird family allows K-9 to become more sustainable and gives us the resources to implement long-requested features and fixes that our users want,' Sipes said. Thunderbird is a free and open-source email, calendaring, newsfeed, and chat client with more than 20 million active monthly users across Windows, macOS, and Linux.Ĭurrently, Android mobile users have a number of email and chat options, including Google’s Gmail, Microsoft Outlook, and ProtonMail, an end-to-end encrypted email service. (Ketterer is better known in the Mozilla open-source developer community as cketti.) “Ultimately, K-9 Mail will transform into Thunderbird on Android, once certain development milestones have been achieved which align it closely with Thunderbird's feature set and visual appearance,” K-9 Mail Project Maintainer Christian Ketterer said in a blog post. (K-9 Mail is available for download through these various sites.) Those planned improvements include account setup using Thunderbird account auto-configuration, as well as folder management, support for message filters, and synchronization between desktop and mobile versions of Thunderbird, Mozilla said. The development team for MZLA Technologies plans to improve the email feature set to more closely resemble that of its Thunderbird desktop email client.

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