Studio is an administration tool for MapServer. It allows to manage MapServer mapfiles, using an easy-to-use web interface.
Studio provides graphical tools, such as sliders and color pickers, for editing styles and symbols. It also provides a tool for automatic classification, and allows saving layers as templates for reuse.
Studio is covered by the GPLv3 open-source license.
See the Studio documentation at http://camptocamp.github.com/Studio/.