A system and method for interactively sharing, synchronizing and controlling information among a plurality of users with different electronic contact types using network-based communication between a plurality of client applications on a plurality of mobile devices and a central controller computer, are described. In an exemplary embodiment, an information context may be configured as open by a first client application. A plurality of client applications may then share information within the information context whereby the plurality of client applications may join the information context using the information context identifier. A method for synchronization allows for shared information on different client devices to be controlled and automatically synchronized by the central controller. Messages, data structures, communications, and protocols between clients and the central controller allowing at least the creation, update, and deletion of information data related to the event, are described.