Abstract: User interface (UI) customization systems and methods are described. A system modifies guest instructions using a first UI style to generate first customized guest instructions that are customized for use by a first client device, and provides the first customized guest instructions to the first client device. The first customized guest instructions include a first customized variant of a UI element with the first UI style applied, and that initiates a function in response to an interaction. The system modifies the guest instructions using a second UI style to generate second customized guest instructions that are customized for use by a second client device, and provides the second customized guest instructions to the second client device. The second customized guest instructions include a second customized variant of the UI element with the second UI style applied, and that initiates the function in response to an interaction.

Abstract: Systems and methods are disclosed for updating an application's user interface (UI) without updating the application. A system provides, for a client device, an application with host instructions having host memory and a guest environment having guest memory. The system receives guest instructions relating to an update to a UI element to be presented via the application's UI without the application being updated. The system selects, based on the client device's platform, a native UI type for the UI element, selected from possible UI types corresponding to different platforms. The system bridges an interaction between a function of the guest instructions and a function of the host instructions without the guest memory and the host memory sharing memory. The system causes the application to display, via the UI, the UI element according to the native UI type based on the bridging and without the application being updated.