A browser-based multilingual IMAP client with an application-like user interface. It provides full functionality you expect from an email client, including MIME support, address book, folder manipulation, message searching and spell checking. More information.
Features:
Multilanguage Address Book Richtext/HTML Canned Responses Shared Folders Plug-In API
Requirements:
PHP 5.4.1 to 7-4 MySQL 5.6 or higher or PostgreSQL 9 or higher or SQLite 3.26 op higher mbstring FileInfo OpenSSL JSon iconv XML Zip