Techniques for execution of multiple application programs and their variations are disclosed. One or more individual application program components that are determined to be already stored and/or loaded into memory are not loaded into memory again, thereby allowing the associated application program to be executed without unnecessarily reloading the one or more individual application program components into memory. Generally, by keeping track and/or predicting of the application components loaded into memory, it can be determined whether to load or unload a particular application program component. In addition, data that can readily identify the application components that are not already into memory can be provided as differential application data for loading various application programs and their variations to facilitate switching between and/or concurrently running multiple application programs and their variations.