K-9 is an open source email client for Android with multi-folder sync, email signatures, Bcc-to-self, return-address configuration, keyboard shortcuts, Exchange Support, message flagging, IMAP deletes, saving attachments, configurable notifications and more.
Comments about K-9 Mail as an Alternative to Thunderbird
Comment summary: K-9 Mail serves as a strong alternative to Thunderbird for Android devices, praised for its OpenKeyChain integration and PGP encryption. It is valued for being open source and user-friendly with options for both POP3 and IMAP. However, criticism centers around its exclusivity to Android, which limits its capability to fully replace desktop-focused Thunderbird for some users.
Top Positive Comment
Top Negative Comment
ByteRanger
K-9 Mail is not for desktop operating systems, only Android. So you can't replace Thunderbird unless you are also replacing your desktop with a mobile device.
jondemon
K9 has nothing to do here. It's an android app
Most users think K-9 Mail is a great Thunderbird alternative.
K-9 Mail is the most popular Android & Android Tablet alternative to Thunderbird.
K-9 Mail is the most popular Open Source & free alternative to Thunderbird.
- K-9 Mail is Free and Open Source
- K-9 Mail is Lightweight
United Kingdom
Keeps the style of working with email as it should be, like we are used to from proper desktop Mail clients. It's unlike modern fancy clients with couple of buttons without even providing an option to view headers.