A system for interfacing at least one user interactive device with a trade execution system to execute trading transactions requested by users over a network includes an application in communication with the network for interfacing between the at least one user interactive device and the trade execution system and coordinating interaction of the at least one user interactive device with the trade execution system. The application contains first and second APIs. The first API is structured to deliver a trading transaction request received from the at least one user interactive device to the trade execution system. The second API is structured to deliver real-time information relating to the trading transaction request received from the trade execution system to the at least one user interactive device. The first API includes at least one stub that is called by the application at a predefined step during processing of the trading transaction request. The at least one stub includes code to interface the application with the trade execution system.