Thunderbird is a seasoned and well respected email client which consistently performs well in Linux. It is a cross platform email client and works in Linux, Mac and Windows. The biggest plus point of Thunderbird is its flexibility. Thunderbird can be customized using add-ons and there are thousands of them. You can import address books, mail filters, Outlook PST files and even skin it to look like Microsoft Outlook. Recently there has been a spurt in new add-ons which is greatly improving Thunderbird’s experience.
Thunderbird comes as a mail client only, calendar support can be added via Lightning addon. It supports POP, IMAP accounts and can automatically pick up configurations from the internet, can auto-configure GMail and Yahoo! e-mail accounts. Recently, it has gained support for MS Exchange accounts and addressbook via add-ons ExQuilla (60 day free trial) and calendar support via Provider for Microsoft Exchange. It also supports Google Chat integration.
However, Thunderbird isn’t without drawbacks. One of the big drawback is its mail composer and the mail list view windows which need a facelift and some bug quashing. Apart from that, Lightning calendar add-on does not integrate into the GNOME desktop like Evolution’s calendar does; so it cannot be used as the default calender app (which is a shame really!). There have been calls for changes but no work has been done so far by Mozilla. This is due to the decision by Mozilla to stop adding any new feature and only concentrate on stability and bug fix releases. My vote for the best Linux desktop email client still goes to Thunderbird for its extensive add-on library, flexibility and features. Thunderbird comes pre-installed in Ubuntu, Linux Mint and is available in the repository for all other Linux distributions.