This paper addresses the inter-operability problem of multimedia terminal in media content delivery over heterogeneous networks and devices. We design and implement a terminal which includes a content browser providing presentation, navigation and interaction with MPEG-21 Digital Item Declaration (MPEG-21 DID) in order to support universal media access (UMA). We optimized the architecture in a client-server distributed approach with Web Service support. This terminal enables the MPEG-21 standard compliant content accessible on different terminal devices via common Web browsers. Such a design strategy illustrates a next-generation multimedia terminal supporting inter- operability in multimedia content adaptation over a heterogeneous delivery chain.