1. A computing device configured to execute a cross-platform application, comprising: a computing device on which an operating system is installed that creates a computing environment, the computing device comprising local storage; an Application Platform application, where the Application Platform application is at least partially natively implemented and creates an application runtime environment when executed by the computing device, the Application Platform application comprising: a rendering engine process configured to: render pages within the computing environment created by the operating system by interpreting instructions written in a rendering language; and implement a virtual machine configured to execute instructions written in a scripting language; and an integration process configured to enable the cross-platform application to communicate with operating system processes; a cross-platform application, where the cross-platform application is configured to be executed within the application runtime environment, is not natively executable by the computing device, and comprises: a text file containing instructions for rendering the cross-platform application in a rendering language configured to be rendered by the Application Platform application; and a text file containing a background page comprising the logic of the cross-platform application written in a scripting language configured to be executed within the application runtime environment created by the Application Platform application; wherein the Application Platform application is configured to integrate the cross-platform application into the computing environment of the computing device by providing at least one launch point for the cross-platform application within the computing environment using the integration process; and wherein the Application Platform application is configured to cache a local version of a portion of the cross-platform application using the local storage so that the cross-platform application can be executed in the absence of a network connection.