1. A method of virtualizing an application, the method comprising: creating a plurality of input configuration files, each input configuration file corresponding to a different operating system of a plurality of operating systems, each input configuration file comprising a collection of configurations made to a computing device executing the corresponding operating system by the installation of the application on the computing device; combining the plurality of input configuration files into an application template; and providing the application template to a virtual application executable constructor operable by a user and configured to use the application template to build a virtualized application executable configured to execute on the plurality of operating systems without installation.