1. A proxy server for adaptively rendering a multimedia content stream, comprising: a first interface for connecting the proxy server to a multimedia network server to receive an original multimedia content stream; a second interface for connecting the proxy server to a client for receiving a rendered multimedia content stream within a mobile device; processing logic for determining rendering parameters responsive to connection parameters related to connection bandwidth and a transport path between the proxy server and the client, charging policies associated with the client and traffic policies associated with a network providing a connection between the proxy server and the client using a multidimensional minimization algorithm, wherein the rendering parameters change in real-time responsive to real-time changes of the connection parameters, the charging policies and the traffic policies; and rendering logic for rendering the rendered multimedia content stream from the original multimedia content stream responsive to the determined rendering parameters that are changing in real-time.