The present invention relates to systems and method for synchronizing collaborative web applications, such as collaborative form filling using a message bus server and HTTP protocol. The method includes delivering compatible plug-ins to a first and a second user so that the users may substantially simultaneously access compatible plug-ins and operate the plug-ins in a coordinated substantially synchronized manner for modifying and/or observing a common file. The process includes delivering a collaborative form to the users. Following the modification of the collaborative form by one of the users, the modification is communicated to a different user. The communication is substantially simultaneous with the modification and takes place by serializing the modification to string and sending the string using HTTP.