Abstract: The present invention monitors usage of an operating system at an application program interface (“API”) level and monitors changes in API functionality associated with an upcoming release to manage the version change process. A computer system is configured to track a collection of API functions associated with a first version operating system currently installed and to record the subset of API functions that have been called by applications during operation of the first version operating system. The computer system is further configured to manage the subset of API functions and generate a comparison between the subset and a list of API functions that have changed between a second version and the first version operating system. Finally, the computer system is configured to report the result of the comparison back to the user.