Abstract: A multi-user computing device, such a communal computing device like an interactive digital whiteboard, can execute single user aware (“SUA”) applications and multi-user aware (“MUA”) applications. Instances of SUA applications execute in the context of a single user. MUA applications can execute in the contexts of multiple authenticated users simultaneously. A multi-user aware OS platform authenticates and de-authenticates users of the multi-user computing device. The multi-user aware OS platform provides notifications to MUA applications when users are authenticated and de-authenticated. When a new user is authenticated, MUA applications begin executing in the context of the newly authenticated user and any other previously authenticated users. When users are de-authenticated, MUA applications stop executing in the context of the de-authenticated user but continue executing in the context of the remaining authenticated users of the multi-user computing device.

Abstract: Techniques for an application interaction platform are described. In at least some implementations, an instance of a first application can initiate a launch of an instance of a second application. In a scenario where the second application is a multiuser application, the second application can be launched as either a multiuser instance or a single user instance depending on a launch context. Implementations also enable communication among applications, such as to enable applications to exchange state information and modify their execution based on the information.

Abstract: Techniques for multiuser application platform are described. Generally, a multiuser application allow interaction by multiple different users with a single executing instance of the application. Implementations include a multiuser operating system and a multiuser application programming interface that enable interaction by multiple users with an executing instance of a multiuser application.

Abstract: A computer device is provided that includes a processor and non-volatile memory including stored instructions executable by the processor, the stored instructions being configured to cause the processor to execute an operating system including an application programming interface for an on-demand installer that is callable by installed application programs during run-time. The on-demand installer is configured to receive a request from an application program to install a target resource package of the application program, query an installer server that is a source of an application program package of the application program to retrieve the target resource package from the installer server, and install the target resource package of the application program.

Abstract: A multi-user computing device, such a communal computing device like an interactive digital whiteboard, can execute single user aware (“SUA”) applications and multi-user aware (“MUA”) applications. Instances of SUA applications execute in the context of a single user. MUA applications can execute in the contexts of multiple authenticated users simultaneously. A multi-user aware OS platform authenticates and de-authenticates users of the multi-user computing device. The multi-user aware OS platform provides notifications to MUA applications when users are authenticated and de-authenticated. When a new user is authenticated, MUA applications begin executing in the context of the newly authenticated user and any other previously authenticated users. When users are de-authenticated, MUA applications stop executing in the context of the de-authenticated user but continue executing in the context of the remaining authenticated users of the multi-user computing device.

Abstract: A computer device is provided that includes a processor and non-volatile memory including stored instructions executable by the processor, the stored instructions being configured to cause the processor to execute an operating system including an application programming interface for an on-demand installer that is callable by installed application programs during run-time. The on-demand installer is configured to receive a request from an application program to install a target resource package of the application program, query an installer server that is a source of an application program package of the application program to retrieve the target resource package from the installer server, and install the target resource package of the application program.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.

Abstract: Techniques for an application interaction platform are described. In at least some implementations, an instance of a first application can initiate a launch of an instance of a second application. In a scenario where the second application is a multiuser application, the second application can be launched as either a multiuser instance or a single user instance depending on a launch context. Implementations also enable communication among applications, such as to enable applications to exchange state information and modify their execution based on the information.

Abstract: Techniques for multiuser application platform are described. Generally, a multiuser application allow interaction by multiple different users with a single executing instance of the application. Implementations include a multiuser operating system and a multiuser application programming interface that enable interaction by multiple users with an executing instance of a multiuser application.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.

Abstract: An integrated media user interface is described. In an implementation, a user interface is output that includes a plurality of representations of media, each of the media rendered by the mobile device through execution of a respective one of a plurality of applications. Responsive to selection of at least one of the representations, a corresponding application is located to render the media represented by the at least one said representation. The media represented by the selected representation is rendered through execution of the located application.