diff --git a/client/src/mobile/components/MRail.tsx b/client/src/mobile/components/MRail.tsx
index c80ac4733..4121a8792 100644
--- a/client/src/mobile/components/MRail.tsx
+++ b/client/src/mobile/components/MRail.tsx
@@ -97,6 +97,11 @@ export function MRailSpacer() {
 interface MRailButtonProps {
   label: string;
   active: boolean;
+  /**
+   * Opens a sheet rather than a section (More): while that sheet is open the button wears
+   * the ring the phone dock's More wears, so the rail says where the sheet came from.
+   */
+  expanded?: boolean;
   onClick: () => void;
   /** The icon, drawn at 20px. */
   children: ReactNode;
@@ -108,19 +113,24 @@ interface MRailButtonProps {
  * and never shrunk: it wraps into a second, balanced line where its language
  * needs one, and only a word longer than the rail is hyphenated.
  */
-export function MRailButton({ label, active, onClick, children }: MRailButtonProps) {
+export function MRailButton({ label, active, expanded, onClick, children }: MRailButtonProps) {
   return (
     <button
       type="button"
       onClick={onClick}
       title={label}
       aria-current={active ? 'page' : undefined}
+      aria-expanded={expanded}
       className="group flex w-full flex-none flex-col items-center gap-[3px] rounded-[18px] py-[5px] outline-none focus-visible:ring-2 focus-visible:ring-[color:var(--m-act)]"
     >
       <span
         aria-hidden="true"
         className={`flex h-10 w-10 items-center justify-center rounded-full transition-colors duration-150 ${
-          active ? 'bg-m-act text-m-actfg' : 'text-m-muted group-hover:bg-[color:var(--m-ic)] group-hover:text-m-ink'
+          active
+            ? 'bg-m-act text-m-actfg'
+            : expanded
+              ? 'bg-[color:var(--m-ic)] text-m-ink ring-[1.5px] ring-inset ring-[color:var(--m-act)]'
+              : 'text-m-muted group-hover:bg-[color:var(--m-ic)] group-hover:text-m-ink'
         }`}
       >
         {children}
diff --git a/client/src/mobile/screens/trip/MTripRail.tsx b/client/src/mobile/screens/trip/MTripRail.tsx
index d5e983bf9..b39735e7a 100644
--- a/client/src/mobile/screens/trip/MTripRail.tsx
+++ b/client/src/mobile/screens/trip/MTripRail.tsx
@@ -16,6 +16,8 @@ interface MTripRailProps {
   onSelect: (id: string) => void;
   /** Opens the More sheet: trip settings, export, the assistant. */
   onMore: () => void;
+  /** Whether the More sheet is open, which the More button shows with a ring. */
+  moreOpen?: boolean;
   labelOf: (id: string) => string;
 }
 
@@ -27,7 +29,7 @@ const DOCK_ICONS = new Map(DOCK_PRIORITY.map((tab) => [tab.id, tab.icon]));
  * collaboration and plugin pages sit in it too, each with its name, and More
  * keeps only the trip's actions.
  */
-export default function MTripRail({ tabs, active, onSelect, onMore, labelOf }: MTripRailProps) {
+export default function MTripRail({ tabs, active, onSelect, onMore, moreOpen = false, labelOf }: MTripRailProps) {
   const { t } = useTranslation();
   return (
     <MRail label={t('mobileTrip.sections')}>
@@ -41,7 +43,7 @@ export default function MTripRail({ tabs, active, onSelect, onMore, labelOf }: M
         );
       })}
       <MRailSpacer />
-      <MRailButton label={t('mobileTrip.more')} active={false} onClick={onMore}>
+      <MRailButton label={t('mobileTrip.more')} active={false} expanded={moreOpen} onClick={onMore}>
         <MoreHorizontal size={20} strokeWidth={2.2} />
       </MRailButton>
     </MRail>
diff --git a/client/src/mobile/screens/trip/MTripShell.tsx b/client/src/mobile/screens/trip/MTripShell.tsx
index 30d86be58..15bc756c2 100644
--- a/client/src/mobile/screens/trip/MTripShell.tsx
+++ b/client/src/mobile/screens/trip/MTripShell.tsx
@@ -901,6 +901,7 @@ export default function MTripShell({
           active={trTab}
           onSelect={setTrTab}
           onMore={() => openSheet('mehr')}
+          moreOpen={sheet?.id === 'mehr'}
           labelOf={tabLabel}
         />
       )}
diff --git a/client/tests/unit/mobile/MNavRail.test.tsx b/client/tests/unit/mobile/MNavRail.test.tsx
index 5146863f0..eb8bc6001 100644
--- a/client/tests/unit/mobile/MNavRail.test.tsx
+++ b/client/tests/unit/mobile/MNavRail.test.tsx
@@ -190,6 +190,24 @@ describe('MTripRail', () => {
     fireEvent.click(within(nav).getByRole('button', { name: 'More' }));
     expect(onMore).toHaveBeenCalledOnce();
   });
+
+  it('FE-MOB-RAIL-014: More wears a ring while its sheet is open, and says it is expanded', () => {
+    const props = {
+      tabs,
+      active: 'plan',
+      onSelect: vi.fn(),
+      onMore: vi.fn(),
+      labelOf: (id: string) => tabs.find((x) => x.id === id)?.label ?? id,
+    };
+    const { rerender } = render(<MTripRail {...props} />);
+    const more = () => screen.getByRole('button', { name: 'More' });
+    expect(more()).toHaveAttribute('aria-expanded', 'false');
+    expect(more().firstElementChild?.className).not.toContain('ring-');
+    rerender(<MTripRail {...props} moreOpen />);
+    expect(more()).toHaveAttribute('aria-expanded', 'true');
+    expect(more().firstElementChild?.className).toContain('ring-[color:var(--m-act)]');
+    expect(more()).not.toHaveAttribute('aria-current');
+  });
 });
 
 describe('MobileShell on a wide window', () => {