Developing a mobile integration for mobile money transfer is non-trivial and requires significant testing and validation before go-live. DonRiver Inc., in partnership with Western Union, developed a complete set of simulation and testing tools to allow mobile carriers to emulate their own local Western Union money transfer systems. Thus allowing them to accelerate their systems integration and fully validate their solutions before requiring any live connectivity with the Western Union production environments. The tools not only simulate the Western Union system, but also allow for full transaction visibility and debugging and problem determination.