bluelatex.org
\BlueLaTeX - Welcome!Real-Time Collaborative Document Edition. BlueLaTeX aims to provide a tool chain to easily write documents collaboratively. The first intended audience of BlueLaTeX is the academic world (for now! By integrating concepts and lifecycles particularly well-suited for these kind of documents, but it can be used for any other kind of document. BlueLaTeX is licensed under the Apache License 2.0. BlueLaTeX is still in beta version and not intended for production yet. Any feedback. Published on 8 May 2015).
http://www.bluelatex.org/
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