1. A flexible, multi-modal system useful in communications among users, capable of synchronizing real world and augmented reality, wherein the system is deployed in centralized and distributed computational platforms, the system comprising: (a) a plurality of communication devices that transmit signals representing the location of a user, speech from a user, and gestures of a user, and that receive signals representing information; (b) a plurality of agents that receive signals from one or more of said communication devices, translate said signals into system-specific data, and compare said data to a database to determine further action of the system, wherein said further action comprises (i) obtaining additional information from one of the said communication devices; (ii) sending a message to another of said communication devices; or (iii) controlling an object that receive signals from the system of the present invention; wherein at least one of the agents generates signals representing meanings as defined by the database, and transmits the signals to a multi-modal interface having a modifiable default mode for types of signals received or generated thereby; and wherein at least one of the agents is a location-monitoring agent that modifies the default mode of the multi-modal interface to another mode based upon the location changes of users, and communicates said modification to the multi-modal interface to modify the default mode of signals generated thereby; and wherein at least one agent is located on computing hardware remote from at least one other agent; and (c) wherein the plurality of agents further comprise: (i) a mapping agent, said agent comprising a geographical internal space being defined by relative local coordinates; said mapping agent receiving location information from one of said communication devices, and translating the same to system relative local coordinates; and (ii) a collision detection agent, said agent being coupled with a database comprising known objects or structures and their location in the geographical internal space, wherein said agent receives orientation, azimuth and pitch information from the multi-modal interface or another agent, and location information from the multi-modal interface or the mapping agent, and using the location information and the direction information, determines which objects if any are intersected by a ray in the azimuth and pitch of the direction information, originating from a vector of the location information.