Ensignia is a modified version of SquirrelMail with an integrated skinning engine, support for mobile devices and some additional functionality (like drag-and-drop) that improve the user experience. The core of the program has not been modified and Ensignia continues to support all the SquirrelMail functionality, plugins and language packs. It is also compatible with SquirrelMail's config and user preferences, which makes upgrading SquirrelMail to Ensignia transparent to the users.