You can use the dashboard's view settings to control aspects of the dashboard's behavior, specific to that view. To open the View pane, click the View button 
on the action bar. To open the view settings, click the Settings tab in the View pane.
Desktop and mobile views
For the desktop view, you can turn on the Allow element re-size toggle button to allow dashboard viewers to manually resize elements.
For both desktop and mobile views, you can turn on the Allow dashboard reset toggle button to allow dashboard viewers to reset the dashboard after making selections and interacting with elements. The reset button only appears when there has been an interaction with the dashboard. Resetting the dashboard clears any selections made on elements, returns the map to its default extent and all map tools to their defaults, and sets any tabs and feature based elements back to their first value.
URL parameters
You can use URL parameters to make dashboards dynamic. With URL parameters, a dashboard can power any number of views. A URL parameter is a property that is added to a dashboard's configuration by its author that can be used to trigger actions.
Learn more about URL parameters and how to configure actions on URL parameters.
Splash screen
You can use a splash screen to provide dashboard viewers with important information before they interact with the dashboard. A splash screen can display text, images, and links, making it useful for introductions, instructions, disclaimers, or other contextual information.