diff --git a/src/components/__tests__/radio-options.test.ts b/src/components/__tests__/radio-options.test.ts
new file mode 100644
index 00000000..e928627f
--- /dev/null
+++ b/src/components/__tests__/radio-options.test.ts
@@ -0,0 +1,37 @@
+// The undo-send delay chips (and the other Composer choices), the Files sort
+// sheet and the language list drew the picked option in another colour only:
+// a screen reader heard every option alike and couldn't tell which was set.
+import { describe, expect, it } from 'vitest';
+import fs from 'node:fs';
+import path from 'node:path';
+import { radioOptionA11y, RADIO_GROUP_A11Y } from '../radio-a11y';
+
+const SRC = path.resolve(__dirname, '../..');
+const read = (rel: string) => fs.readFileSync(path.join(SRC, rel), 'utf8').split('\r\n').join('\n');
+
+describe('radioOptionA11y', () => {
+  it('gives the picked option the radio role and the selected and checked state', () => {
+    expect(radioOptionA11y(true)).toEqual({ accessibilityRole: 'radio', accessibilityState: { selected: true, checked: true } });
+    expect(radioOptionA11y(false).accessibilityState).toEqual({ selected: false, checked: false });
+    expect(RADIO_GROUP_A11Y.accessibilityRole).toBe('radiogroup');
+  });
+});
+
+describe('option groups', () => {
+  it('Composer chips (undo-send delay, autosave, signature) say which one is set', () => {
+    const source = read('components/settings/ComposingSettings.tsx');
+    const segmented = source.slice(source.indexOf('const segmented'), source.indexOf('return (\n    <SettingsSection'));
+    expect(segmented).toContain('{...RADIO_GROUP_A11Y}');
+    expect(segmented).toContain('{...radioOptionA11y(active)}');
+  });
+
+  it('the Files sort sheet says which order is set', () => {
+    const source = read('screens/FilesScreen.tsx');
+    expect(source).toContain('{...radioOptionA11y(sortKey === k)}');
+    expect(source).toContain('{...radioOptionA11y(sortDir === d)}');
+  });
+
+  it('the language list says which language is set', () => {
+    expect(read('components/settings/LanguageSettings.tsx')).toContain('{...radioOptionA11y(active)}');
+  });
+});
diff --git a/src/components/radio-a11y.ts b/src/components/radio-a11y.ts
new file mode 100644
index 00000000..06a6b0b1
--- /dev/null
+++ b/src/components/radio-a11y.ts
@@ -0,0 +1,17 @@
+// One choice of a set of options (the undo-send delay, the Files sort order,
+// the app language). Drawn as a styled Pressable, an option told a screen
+// reader nothing about which one was picked: TalkBack read "5 seconds" for
+// every chip alike. A radio role with the selected and checked state reads
+// "selected" (Android) or "checked" (iOS) on the current one.
+
+export interface RadioOptionA11y {
+  accessibilityRole: 'radio';
+  accessibilityState: { selected: boolean; checked: boolean };
+}
+
+export function radioOptionA11y(selected: boolean): RadioOptionA11y {
+  return { accessibilityRole: 'radio', accessibilityState: { selected, checked: selected } };
+}
+
+/** For the View around the options. */
+export const RADIO_GROUP_A11Y = { accessibilityRole: 'radiogroup' } as const;
diff --git a/src/components/settings/ComposingSettings.tsx b/src/components/settings/ComposingSettings.tsx
index 50d49c30..abd83843 100644
--- a/src/components/settings/ComposingSettings.tsx
+++ b/src/components/settings/ComposingSettings.tsx
@@ -8,6 +8,7 @@ import { useColors } from '../../theme/colors';
 import { useSettingsStore, type ReplyIdentityMatch, type SignaturePosition } from '../../stores/settings-store';
 import { useLocaleStore } from '../../stores/locale-store';
 import { SUPPORTED_SUB_ADDRESS_DELIMITERS } from '../../lib/sub-addressing';
+import { RADIO_GROUP_A11Y, radioOptionA11y } from '../radio-a11y';
 
 export function ComposingSettings() {
   const c = useColors();
@@ -82,12 +83,13 @@ export function ComposingSettings() {
     current: T,
     onPick: (value: T) => void,
   ) => (
-    <View style={styles.segmentRow}>
+    <View style={styles.segmentRow} {...RADIO_GROUP_A11Y}>
       {options.map((opt) => {
         const active = current === opt.value;
         return (
           <Pressable
             key={String(opt.value)}
+            {...radioOptionA11y(active)}
             onPress={() => onPick(opt.value)}
             style={[styles.segment, active && styles.segmentActive]}
           >
diff --git a/src/components/settings/LanguageSettings.tsx b/src/components/settings/LanguageSettings.tsx
index 320da97d..0a43cf9f 100644
--- a/src/components/settings/LanguageSettings.tsx
+++ b/src/components/settings/LanguageSettings.tsx
@@ -8,6 +8,7 @@ import { useLocaleStore } from '../../stores/locale-store';
 import { useSettingsStore, type DateFormat, type TimeFormat } from '../../stores/settings-store';
 import { formatListDate } from '../../lib/date-format';
 import { SUPPORTED_LOCALES, detectDeviceLocale, type LocaleCode } from '../../i18n';
+import { radioOptionA11y } from '../radio-a11y';
 
 export function LanguageSettings() {
   const c = useColors();
@@ -43,6 +44,7 @@ export function LanguageSettings() {
     return (
       <Pressable
         key={code}
+        {...radioOptionA11y(active)}
         onPress={() => setOverride(code === 'system' ? null : (code as LocaleCode))}
         style={({ pressed }) => [styles.row, pressed && styles.rowPressed]}
       >
diff --git a/src/screens/FilesScreen.tsx b/src/screens/FilesScreen.tsx
index d9c040d0..8aafeb73 100644
--- a/src/screens/FilesScreen.tsx
+++ b/src/screens/FilesScreen.tsx
@@ -72,6 +72,7 @@ import { formatListDate } from '../lib/date-format';
 import { useLayout, useSheetInsets } from '../lib/use-layout';
 import { useSheetBottomInset } from '../lib/sheet-bottom-inset';
 import { filesListWidth } from '../lib/files-split';
+import { radioOptionA11y } from '../components/radio-a11y';
 import { useBackWhileFocused } from '../lib/use-back-while-focused';
 import { filesBackStep } from '../lib/files-back';
 import { driveChange, type DriveScope } from '../lib/files-drive';
@@ -2148,7 +2149,7 @@ function SortSheet({ visible, sortKey, sortDir, t, onClose, onChangeKey, onChang
             <View style={[styles.sheet, { paddingBottom: spacing.xxl + bottomInset }]}>
               <Text style={styles.sheetTitle}>{t('files.settings_default_sort', 'Sort')}</Text>
               {keys.map((k) => (
-                <Pressable key={k} style={styles.action} onPress={() => { onChangeKey(k); onClose(); }}>
+                <Pressable key={k} style={styles.action} {...radioOptionA11y(sortKey === k)} onPress={() => { onChangeKey(k); onClose(); }}>
                   <Text style={[styles.actionLabel, sortKey === k && { color: c.primary, fontWeight: '600' }]}>
                     {t(`files.${k}`, k)}
                   </Text>
@@ -2157,7 +2158,7 @@ function SortSheet({ visible, sortKey, sortDir, t, onClose, onChangeKey, onChang
               ))}
               <View style={styles.sheetDivider} />
               {(['asc', 'desc'] as FilesSortDir[]).map((d) => (
-                <Pressable key={d} style={styles.action} onPress={() => { onChangeDir(d); onClose(); }}>
+                <Pressable key={d} style={styles.action} {...radioOptionA11y(sortDir === d)} onPress={() => { onChangeDir(d); onClose(); }}>
                   {d === 'asc' ? <ArrowUp size={18} color={c.text} /> : <ArrowDown size={18} color={c.text} />}
                   <Text style={[styles.actionLabel, sortDir === d && { color: c.primary, fontWeight: '600' }]}>
                     {d === 'asc'