Abstract: A computer program product embodied in a computer-readable medium is configurable to accomplish execution of an application that is specified and encoded in a markup-based descriptor language. The product includes client runtime computer code configured to cause a client computer device to process the markup-based descriptor language to deploy an application to accomplish execution of the application. The client runtime computer code is further configured to process the markup-based descriptor language to selectively configure the client computer device to deploy the application so as to accomplish execution of the application by the client computer device stand-alone or by the client computer device in cooperation with a server to which the device is connectable via a network connection.