Returns

Name	Type	Description
isMobile	boolean	Whether the current viewport is below the AppShell mobile navigation breakpoint. Use this to synchronize AppShell-adjacent mobile UI with the same breakpoint as mobile nav.
isMobileNavOpen	boolean	Whether the AppShell-managed mobile navigation drawer is open.
mobileNavId	string | undefined	DOM id of the mobile navigation drawer, set by AppShell. Point aria-controls of a custom toggle at this so screen-reader users know which element the toggle expands. Undefined outside an AppShell that manages the drawer.
toggleMobileNav	() => void	Toggle the AppShell-managed mobile navigation drawer. No-ops when mobile nav is disabled.
openMobileNav	() => void	Open the AppShell-managed mobile navigation drawer. No-ops when mobile nav is disabled.
closeMobileNav	() => void	Close the AppShell-managed mobile navigation drawer.
isMobileNavEnabled	boolean	Whether AppShell mobile navigation is enabled and managed by AppShell. False when mobileNav is false, there is no nav content, or a fully custom mobileNav slot owns the drawer.
hasAutoToggle	boolean	Whether AppShell auto-toggle behavior is enabled. False when mobileNav.hasToggle is set to false; combine with isMobile and isMobileNavEnabled before rendering custom toggles.
hasSideNav	boolean	Whether the AppShell has a sideNav slot. Mobile navigation is only managed when there is nav content to show.

The returned object is stable and reactive. Read the fields in a template or a computed and they follow the AppShell as the viewport changes.