Horde Webmail is even more of a collaborative framework of services. And since June 14, a new version of Horde is out. This is version 4, which is a major new release.
The following new features and changes improved overall Horde 4 performance.
* Completely rewritten in PHP 5
* New installation procedure through a PEAR installer
* Simplifying the configuration process
* Support for ActiveSync
* Layout without frames
* Group preferences
* Improving the cache and reducing the size of the sessions.
* Shared libraries are faster
* Reducing dependencies on external libraries
* Many miscellaneous improvements.
* Many interface improvements including a vertical side panel
* Complete rewrite of IMAP support for better support and a great performance improvement
* Increased and improved filter capabilities and research
* Rapid response capability
* Improved notifications of new posts
* Better display of HTML mail
* HTML Signature
* Automatic saving of drafts
* Support for custom IMAP flags
* Reduced memory usage
* Search for duplicates and opportunities to merge contacts
* New AJAX interface with integrated task management
* New interface for mobile
* Resource planning
* Colorization of the calendar
* Tagging system
* Support for cross-timezone
* Support CalDAV
* Reinforced exceptions for recurring events
* Improved messages for notifications and invitations.
* New AJAX interface in the calendar
* System task list
* Colorization task lists
* Quickly add tasks