Streaming multimedia applications over the Internet to mobile device or remote client is still facing the problem of client heterogeneity in terms of bandwidth capacity and user's preferences on the perceived video quality. Addressing this problem, user-friendly active Network system (FANS) is designed and implemented on the basis of active network paradigm where intermediate peer computers adapts the bandwidth consumption of the streaming media heading to the destination into the desired level either by reformatting the media file or rescaling the media presentation size. While FANS proves reliable in reaching the client with poor bandwidth, we need to make obvious that the user interface of the system is simple, self-descriptive and encouraging for the users. The paper is devoted to describe the design considerations, the implementation and the functionality of each user interface components. We identify five attributes that should be considered in designing a user interface for dynamic, multiple locations streaming multimedia environment, which is the case of FANS. The user interface considers thoroughly the five attributes and has been reliably and conveniently used in hundreds of tests of FANS' performance evaluation. Last, the user interface also conforms six principles of the usability heuristic rules.