1. A method for setting up a runtime environment for an application comprising: an application platform of a client software to perform the steps of: determining whether the application is installed; receiving a wake up command for the application by the user; in response to the wake up command and when the application is determined to be installed, creating a process of the application; managing the application's process, by an application center of said application platform, by creating a connecting session between said application center and said process of the application, wherein creating and managing the process of the application further comprises: applying a connecting session identification (ID) for an ID of the application; creating a cross process channel for the application platform according to the connecting session ID; creating a process of the application; and sending the ID of the application to the process of the application; sending a command to activate and load the process of the application according to a feedback indicating the cross process channel for the application is successfully created by the process of the application; and after activating and loading the process of the application, providing an application platform interface for developing the application, wherein said interface allows application developers to use functions of the client software with the application.