An application status system is described herein that informs the user about application-specific status updates and notifications through a changing status icon associated with an application-switching user interface displayed by an operating system when the application is running. When an application has focus, there is typically no way for another application to display status to the user without displaying a dialog box or a notification balloon that interrupts the user. The application status system takes advantage of the existing application-switching user interface to display a lightweight status icon overlay on the application-switching user interface itself. Thus, the application status system allows applications to provide application-specific status updates without interrupting a user's activity in another application and without adding additional UI for a user to process.