Mozilla Thunderbird

Homepage: https://www.mozilla.org/el/thunderbird/

Download link: https://www.mozilla.org/thunderbird/

Operating Systems: Windows Mac OS-X, Linux

Description: Email client software.  Supports: Pop3, Imap, Smtp, extensions, webmail access, spam filtering, anti phishing, spell checking, automatic updates κand many more.

Foxmail

Homepage: http://www.foxmail.com//

Download link: http://www.softpedia.com/get/Internet/E-mail/E-mail-Clients/Foxmail.shtml

Operating Systems: Windows, Mac

Description: Email client software with many features.