diff --git a/src/app/features/lobby/HierarchyItemMenu.tsx b/src/app/features/lobby/HierarchyItemMenu.tsx
index 1802e3b0..cdfa2d8a 100644
--- a/src/app/features/lobby/HierarchyItemMenu.tsx
+++ b/src/app/features/lobby/HierarchyItemMenu.tsx
@@ -30,6 +30,7 @@ import { IPowerLevels } from '../../hooks/usePowerLevels';
 import { getRoomCreatorsForRoomId } from '../../hooks/useRoomCreators';
 import { getRoomPermissionsAPI } from '../../hooks/useRoomPermissions';
 import { InviteUserPrompt } from '../../components/invite-user-prompt';
+import { PhoneHitSpread24 } from '../../styles/PhoneHit.css';
 
 type HierarchyItemWithParent = HierarchyItem & {
   parentId: string;
@@ -231,6 +232,7 @@ export function HierarchyItemMenu({
   return (
     <Box gap="200" alignItems="Center" shrink="No">
       <IconButton
+        className={PhoneHitSpread24}
         onClick={handleOpenMenu}
         size="300"
         variant="SurfaceVariant"
diff --git a/src/app/features/lobby/Lobby.tsx b/src/app/features/lobby/Lobby.tsx
index 2c58b8af..b0ed4282 100644
--- a/src/app/features/lobby/Lobby.tsx
+++ b/src/app/features/lobby/Lobby.tsx
@@ -48,6 +48,7 @@ import { useGetRoom } from '../../hooks/useGetRoom';
 import { AsyncStatus, useAsyncCallback } from '../../hooks/useAsyncCallback';
 import { getRoomPermissionsAPI } from '../../hooks/useRoomPermissions';
 import { getRoomCreatorsForRoomId } from '../../hooks/useRoomCreators';
+import { PhoneHit } from '../../styles/PhoneHit.css';
 
 const useCanDropLobbyItem = (
   space: Room,
@@ -413,6 +414,7 @@ export function Lobby() {
                     onVisibilityChange={setOnTop}
                   >
                     <IconButton
+                      className={PhoneHit}
                       onClick={() => virtualizer.scrollToOffset(0)}
                       variant="SurfaceVariant"
                       radii="Pill"
diff --git a/src/app/features/message-search/MessageSearch.tsx b/src/app/features/message-search/MessageSearch.tsx
index 26085b5f..a1759ef9 100644
--- a/src/app/features/message-search/MessageSearch.tsx
+++ b/src/app/features/message-search/MessageSearch.tsx
@@ -23,6 +23,7 @@ import { SearchResultGroup } from './SearchResultGroup';
 import { SearchInput } from './SearchInput';
 import { SearchFilters } from './SearchFilters';
 import { VirtualTile } from '../../components/virtualizer';
+import { PhoneHit } from '../../styles/PhoneHit.css';
 
 const useSearchPathSearchParams = (searchParams: URLSearchParams): _SearchPathSearchParams =>
   useMemo(
@@ -193,6 +194,7 @@ export function MessageSearch({
     <Box direction="Column" gap="700">
       <ScrollTopContainer scrollRef={scrollRef} anchorRef={scrollTopAnchorRef}>
         <IconButton
+          className={PhoneHit}
           onClick={() => virtualizer.scrollToOffset(0)}
           variant="SurfaceVariant"
           radii="Pill"
diff --git a/src/app/features/room-settings/RoomSettings.tsx b/src/app/features/room-settings/RoomSettings.tsx
index 8601c365..8f96bd7c 100644
--- a/src/app/features/room-settings/RoomSettings.tsx
+++ b/src/app/features/room-settings/RoomSettings.tsx
@@ -17,6 +17,7 @@ import { Permissions } from './permissions';
 import { RoomSettingsPage } from '../../state/roomSettings';
 import { useRoom } from '../../hooks/useRoom';
 import { DeveloperTools } from '../common-settings/developer-tools';
+import { PhoneHit } from '../../styles/PhoneHit.css';
 
 type RoomSettingsMenuItem = {
   page: RoomSettingsPage;
@@ -117,7 +118,7 @@ export function RoomSettings({ initialPage, requestClose }: RoomSettingsProps) {
               </Box>
               <Box shrink="No">
                 {screenSize === ScreenSize.Mobile && (
-                  <IconButton onClick={requestClose} variant="Background">
+                  <IconButton className={PhoneHit} onClick={requestClose} variant="Background">
                     <Icon src={Icons.Cross} />
                   </IconButton>
                 )}
diff --git a/src/app/features/room-settings/general/General.tsx b/src/app/features/room-settings/general/General.tsx
index 15157304..e29fe2da 100644
--- a/src/app/features/room-settings/general/General.tsx
+++ b/src/app/features/room-settings/general/General.tsx
@@ -15,6 +15,7 @@ import {
 } from '../../common-settings/general';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { useRoomPermissions } from '../../../hooks/useRoomPermissions';
+import { PhoneHit } from '../../../styles/PhoneHit.css';
 
 type GeneralProps = {
   requestClose: () => void;
@@ -35,7 +36,7 @@ export function General({ requestClose }: GeneralProps) {
             </Text>
           </Box>
           <Box shrink="No">
-            <IconButton onClick={requestClose} variant="Surface">
+            <IconButton className={PhoneHit} onClick={requestClose} variant="Surface">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>
diff --git a/src/app/features/room-settings/permissions/Permissions.tsx b/src/app/features/room-settings/permissions/Permissions.tsx
index 7572a71b..d513dda9 100644
--- a/src/app/features/room-settings/permissions/Permissions.tsx
+++ b/src/app/features/room-settings/permissions/Permissions.tsx
@@ -9,6 +9,7 @@ import { usePermissionGroups } from './usePermissionItems';
 import { PermissionGroups, Powers, PowersEditor } from '../../common-settings/permissions';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { useRoomPermissions } from '../../../hooks/useRoomPermissions';
+import { PhoneHit } from '../../../styles/PhoneHit.css';
 
 type PermissionsProps = {
   requestClose: () => void;
@@ -45,7 +46,7 @@ export function Permissions({ requestClose }: PermissionsProps) {
             </Text>
           </Box>
           <Box shrink="No">
-            <IconButton onClick={requestClose} variant="Surface">
+            <IconButton className={PhoneHit} onClick={requestClose} variant="Surface">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>
diff --git a/src/app/features/space-settings/SpaceSettings.tsx b/src/app/features/space-settings/SpaceSettings.tsx
index b5fefc93..1030972f 100644
--- a/src/app/features/space-settings/SpaceSettings.tsx
+++ b/src/app/features/space-settings/SpaceSettings.tsx
@@ -17,6 +17,7 @@ import { Members } from '../common-settings/members';
 import { DeveloperTools } from '../common-settings/developer-tools';
 import { General } from './general';
 import { Permissions } from './permissions';
+import { PhoneHit } from '../../styles/PhoneHit.css';
 
 type SpaceSettingsMenuItem = {
   page: SpaceSettingsPage;
@@ -117,7 +118,7 @@ export function SpaceSettings({ initialPage, requestClose }: SpaceSettingsProps)
               </Box>
               <Box shrink="No">
                 {screenSize === ScreenSize.Mobile && (
-                  <IconButton onClick={requestClose} variant="Background">
+                  <IconButton className={PhoneHit} onClick={requestClose} variant="Background">
                     <Icon src={Icons.Cross} />
                   </IconButton>
                 )}
diff --git a/src/app/features/space-settings/general/General.tsx b/src/app/features/space-settings/general/General.tsx
index 72040632..e99a4906 100644
--- a/src/app/features/space-settings/general/General.tsx
+++ b/src/app/features/space-settings/general/General.tsx
@@ -13,6 +13,7 @@ import {
 } from '../../common-settings/general';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { useRoomPermissions } from '../../../hooks/useRoomPermissions';
+import { PhoneHit } from '../../../styles/PhoneHit.css';
 
 type GeneralProps = {
   requestClose: () => void;
@@ -33,7 +34,7 @@ export function General({ requestClose }: GeneralProps) {
             </Text>
           </Box>
           <Box shrink="No">
-            <IconButton onClick={requestClose} variant="Surface">
+            <IconButton className={PhoneHit} onClick={requestClose} variant="Surface">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>
diff --git a/src/app/features/space-settings/permissions/Permissions.tsx b/src/app/features/space-settings/permissions/Permissions.tsx
index 7572a71b..d513dda9 100644
--- a/src/app/features/space-settings/permissions/Permissions.tsx
+++ b/src/app/features/space-settings/permissions/Permissions.tsx
@@ -9,6 +9,7 @@ import { usePermissionGroups } from './usePermissionItems';
 import { PermissionGroups, Powers, PowersEditor } from '../../common-settings/permissions';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { useRoomPermissions } from '../../../hooks/useRoomPermissions';
+import { PhoneHit } from '../../../styles/PhoneHit.css';
 
 type PermissionsProps = {
   requestClose: () => void;
@@ -45,7 +46,7 @@ export function Permissions({ requestClose }: PermissionsProps) {
             </Text>
           </Box>
           <Box shrink="No">
-            <IconButton onClick={requestClose} variant="Surface">
+            <IconButton className={PhoneHit} onClick={requestClose} variant="Surface">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>
diff --git a/src/app/pages/client/explore/Explore.tsx b/src/app/pages/client/explore/Explore.tsx
index dae83166..6944c9f7 100644
--- a/src/app/pages/client/explore/Explore.tsx
+++ b/src/app/pages/client/explore/Explore.tsx
@@ -37,6 +37,7 @@ import { AsyncStatus, useAsyncCallback } from '../../../hooks/useAsyncCallback';
 import { useNavToActivePathMapper } from '../../../hooks/useNavToActivePathMapper';
 import { PageNav, PageNavContent, PageNavHeader } from '../../../components/page';
 import { stopPropagation } from '../../../utils/keyboard';
+import { PhoneHit } from '../../../styles/PhoneHit.css';
 
 export function AddServer() {
   const mx = useMatrixClient();
@@ -96,7 +97,12 @@ export function AddServer() {
                 <Box grow="Yes">
                   <Text size="H4">Add Server</Text>
                 </Box>
-                <IconButton size="300" onClick={() => setDialog(false)} radii="300">
+                <IconButton
+                  className={PhoneHit}
+                  size="300"
+                  onClick={() => setDialog(false)}
+                  radii="300"
+                >
                   <Icon src={Icons.Cross} />
                 </IconButton>
               </Header>
diff --git a/src/app/phoneHit.roomSpace.test.ts b/src/app/phoneHit.roomSpace.test.ts
new file mode 100644
index 00000000..c98c2b09
--- /dev/null
+++ b/src/app/phoneHit.roomSpace.test.ts
@@ -0,0 +1,28 @@
+import { describe, it } from 'vitest';
+import { expectPhoneHitClasses, expectSizeTie } from './phoneHitTestKit';
+
+describe('icon buttons in room settings, space settings, lobby, search and explore', () => {
+  // The class each IconButton must carry, in source order. Vertical stacks and lone buttons: the plain PhoneHit.
+  const expected: Record<string, string[]> = {
+    'features/room-settings/RoomSettings.tsx': ['PhoneHit'], // close, phone only, alone at the header end
+    'features/room-settings/general/General.tsx': ['PhoneHit'], // close, 40 px
+    'features/room-settings/permissions/Permissions.tsx': ['PhoneHit'],
+    'features/space-settings/SpaceSettings.tsx': ['PhoneHit'],
+    'features/space-settings/general/General.tsx': ['PhoneHit'],
+    'features/space-settings/permissions/Permissions.tsx': ['PhoneHit'],
+    // 16 px icon + 8 padding = 24 px, 8-12 px from the Open / Add chips beside it in a hierarchy card
+    'features/lobby/HierarchyItemMenu.tsx': ['PhoneHitSpread24'],
+    'features/lobby/Lobby.tsx': ['PhoneHit'], // floating scroll-to-top, alone
+    'features/message-search/MessageSearch.tsx': ['PhoneHit'], // floating scroll-to-top, alone
+    'pages/client/explore/Explore.tsx': ['PhoneHit'], // Add Server dialog close
+  };
+
+  it.each(Object.entries(expected))(
+    '%s: each IconButton carries its own PhoneHit class',
+    (file, want) => expectPhoneHitClasses(file, want)
+  );
+
+  it.each(Object.keys(expected))('%s: a sized variant matches the drawn size', (file) =>
+    expectSizeTie(file)
+  );
+});