diff --git a/__tests__/inbox-accessibility-labels.test.ts b/__tests__/inbox-accessibility-labels.test.ts
new file mode 100644
index 00000000..05c6065d
--- /dev/null
+++ b/__tests__/inbox-accessibility-labels.test.ts
@@ -0,0 +1,129 @@
+/**
+ * Verifies the Visual Notification Inbox accessibility labels survive the JS -> native hop.
+ *
+ * The labels are plain data on `CioConfig['inApp']`, and the native side does the real work: iOS
+ * parses the dictionary in `MessagingInAppConfigBuilder.build(from:)`, Android converts the
+ * `{count}` template into the `(Int) -> String` the SDK expects.
+ *
+ * Scope: these cover only the JavaScript half — that `initialize` forwards the object intact,
+ * under the key the native parsers read, without interpolating the count. They do NOT pin the
+ * native key names; renaming `bell` in either parser leaves these green while every label stops
+ * arriving. Guarding that needs a test on the native side of each bridge, which on Android would
+ * require a test source set this package does not have.
+ *
+ * `jest.mock` factories are hoisted above module-scope declarations, so each mock is created
+ * inside its factory and read back from the imported (mocked) module.
+ */
+
+// Importing `customerio-cdp` pulls in every sibling module, and each one resolves its TurboModule
+// at import time — so the mock needs TurboModuleRegistry as well as Platform.
+jest.mock('react-native', () => ({
+  Platform: {
+    OS: 'ios',
+    select: (spec: { [key: string]: unknown }) =>
+      spec.ios ?? spec.default ?? undefined,
+  },
+  TurboModuleRegistry: {
+    get: jest.fn(() => null),
+    getEnforcing: jest.fn(() => ({})),
+  },
+  NativeEventEmitter: jest.fn(() => ({
+    addListener: jest.fn(() => ({ remove: jest.fn() })),
+  })),
+}));
+
+// The native Fabric components pull in codegen internals this test does not need.
+jest.mock('../src/components', () => ({}));
+
+jest.mock('../src/native-logger-listener', () => ({
+  NativeLoggerListener: {
+    warn: jest.fn(),
+    initialize: jest.fn(),
+    // customerio-cdp calls this at module scope.
+    initNativeLogger: jest.fn(),
+  },
+}));
+
+jest.mock('../src/specs/modules/NativeCustomerIO', () => ({
+  __esModule: true,
+  default: { initialize: jest.fn(() => Promise.resolve(true)) },
+}));
+
+import { CustomerIO } from '../src/customerio-cdp';
+import NativeModule from '../src/specs/modules/NativeCustomerIO';
+import type { CioConfig } from '../src/types';
+
+const nativeInitialize = NativeModule.initialize as jest.Mock;
+
+const labels = {
+  bell: 'Aviseringar',
+  bellWithUnreadCount: 'Aviseringar, {count} olasta',
+  loadingIndicator: 'Laddar',
+  emptyState: 'Inga aviseringar',
+};
+
+const configWith = (inApp: CioConfig['inApp']): CioConfig =>
+  ({ cdpApiKey: 'test-key', inApp }) as CioConfig;
+
+describe('notification inbox accessibility labels', () => {
+  beforeEach(() => {
+    nativeInitialize.mockClear();
+  });
+
+  it('forwards every label to the native module under the shared config key', async () => {
+    await CustomerIO.initialize(
+      configWith({
+        siteId: 'site',
+        notificationInboxAccessibilityLabels: labels,
+      })
+    );
+
+    const [forwardedConfig] = nativeInitialize.mock.calls[0];
+    expect(forwardedConfig.inApp.notificationInboxAccessibilityLabels).toEqual(
+      labels
+    );
+  });
+
+  it('keeps the {count} placeholder intact for the native side to substitute', async () => {
+    await CustomerIO.initialize(
+      configWith({
+        siteId: 'site',
+        notificationInboxAccessibilityLabels: labels,
+      })
+    );
+
+    const [forwardedConfig] = nativeInitialize.mock.calls[0];
+    // JS must not interpolate: the count is only known natively, at render time.
+    expect(
+      forwardedConfig.inApp.notificationInboxAccessibilityLabels
+        .bellWithUnreadCount
+    ).toContain('{count}');
+  });
+
+  it('omits the labels entirely when the app configures none', async () => {
+    await CustomerIO.initialize(configWith({ siteId: 'site' }));
+
+    const [forwardedConfig] = nativeInitialize.mock.calls[0];
+    // Absent rather than an empty object: the native default is "emit no labels at all",
+    // and nothing in the JS layer should manufacture a value the host did not set.
+    expect(
+      forwardedConfig.inApp.notificationInboxAccessibilityLabels
+    ).toBeUndefined();
+  });
+
+  it('forwards a partial set without filling in the rest', async () => {
+    await CustomerIO.initialize(
+      configWith({
+        siteId: 'site',
+        notificationInboxAccessibilityLabels: {
+          emptyState: 'Inga aviseringar',
+        },
+      })
+    );
+
+    const [forwardedConfig] = nativeInitialize.mock.calls[0];
+    expect(forwardedConfig.inApp.notificationInboxAccessibilityLabels).toEqual({
+      emptyState: 'Inga aviseringar',
+    });
+  });
+});
diff --git a/android/gradle.properties b/android/gradle.properties
index 9010b7b3..2896b287 100644
--- a/android/gradle.properties
+++ b/android/gradle.properties
@@ -2,4 +2,4 @@ customerio.reactnative.kotlinVersion=2.1.20
 customerio.reactnative.compileSdkVersion=36
 customerio.reactnative.targetSdkVersion=36
 customerio.reactnative.minSdkVersion=21
-customerio.reactnative.cioSDKVersionAndroid=4.20.2
+customerio.reactnative.cioSDKVersionAndroid=4.21.1
diff --git a/android/src/main/java/io/customer/reactnative/sdk/constant/Keys.kt b/android/src/main/java/io/customer/reactnative/sdk/constant/Keys.kt
index cb14e3cd..d32c6e61 100644
--- a/android/src/main/java/io/customer/reactnative/sdk/constant/Keys.kt
+++ b/android/src/main/java/io/customer/reactnative/sdk/constant/Keys.kt
@@ -14,7 +14,24 @@ internal object Keys {
         const val SCREEN_VIEW_USE = "screenViewUse"
         const val API_HOST = "apiHost"
         const val CDN_HOST = "cdnHost"
+        const val NOTIFICATION_INBOX_ACCESSIBILITY_LABELS = "notificationInboxAccessibilityLabels"
         // Push messaging
         const val PUSH_CLICK_BEHAVIOR = "pushClickBehavior"
     }
+
+    /**
+     * Keys of the `notificationInboxAccessibilityLabels` sub-map.
+     *
+     * [BELL_WITH_UNREAD_COUNT] carries a template string containing [COUNT_PLACEHOLDER] rather than
+     * a callback, because wrapper configuration crosses a bridge that carries data but not
+     * functions. The native SDK takes a `(Int) -> String`, so the template is converted to one when
+     * the module is configured.
+     */
+    object InboxAccessibilityLabels {
+        const val BELL = "bell"
+        const val BELL_WITH_UNREAD_COUNT = "bellWithUnreadCount"
+        const val LOADING_INDICATOR = "loadingIndicator"
+        const val EMPTY_STATE = "emptyState"
+        const val COUNT_PLACEHOLDER = "{count}"
+    }
 }
diff --git a/android/src/main/java/io/customer/reactnative/sdk/messaginginapp/NativeMessagingInAppModule.kt b/android/src/main/java/io/customer/reactnative/sdk/messaginginapp/NativeMessagingInAppModule.kt
index a8d49bef..9ca2ac7a 100644
--- a/android/src/main/java/io/customer/reactnative/sdk/messaginginapp/NativeMessagingInAppModule.kt
+++ b/android/src/main/java/io/customer/reactnative/sdk/messaginginapp/NativeMessagingInAppModule.kt
@@ -10,6 +10,7 @@ import io.customer.messaginginapp.di.inAppMessaging
 import io.customer.messaginginapp.gist.data.model.InboxMessage
 import io.customer.messaginginapp.gist.data.model.response.InboxMessageFactory
 import io.customer.messaginginapp.inbox.NotificationInbox
+import io.customer.messaginginapp.type.NotificationInboxAccessibilityLabels
 import io.customer.reactnative.sdk.NativeCustomerIOMessagingInAppSpec
 import io.customer.reactnative.sdk.constant.Keys
 import io.customer.reactnative.sdk.extension.getTypedValue
@@ -246,9 +247,62 @@ class NativeMessagingInAppModule(
             val module = ModuleMessagingInApp(
                 MessagingInAppModuleConfig.Builder(siteId = siteId, region = region).apply {
                     setEventListener(eventListener = ReactInAppEventListener.instance)
+                    inboxAccessibilityLabelsFromConfig(config)?.let { labels ->
+                        setNotificationInboxAccessibilityLabels(labels)
+                    }
                 }.build(),
             )
             builder.addCustomerIOModule(module)
         }
+
+        /**
+         * Builds the host's inbox accessibility labels from the wrapper configuration, or null when
+         * the app provided none — in which case the SDK keeps its default of emitting no labels at
+         * all rather than falling back to English.
+         *
+         * `bellWithUnreadCount` arrives as a template string because the bridge carries data but not
+         * functions; it is converted here into the `(Int) -> String` the native SDK expects. A
+         * template without the placeholder is returned verbatim for every count.
+         */
+        private fun inboxAccessibilityLabelsFromConfig(
+            config: Map<String, Any>
+        ): NotificationInboxAccessibilityLabels? {
+            val labels = config.getTypedValue<Map<String, Any>>(
+                Keys.Config.NOTIFICATION_INBOX_ACCESSIBILITY_LABELS
+            ) ?: return null
+
+            val unreadCountTemplate = labels.getTypedValue<String>(
+                Keys.InboxAccessibilityLabels.BELL_WITH_UNREAD_COUNT
+            )
+            // A mistyped placeholder (`{COUNT}`, `{{count}}`, `%d`) substitutes nothing and is read
+            // aloud verbatim, braces included, with the count never announced. Nothing else in the
+            // stack can surface that, so say it here.
+            if (unreadCountTemplate != null &&
+                !unreadCountTemplate.contains(Keys.InboxAccessibilityLabels.COUNT_PLACEHOLDER)
+            ) {
+                SDKComponent.logger.debug(
+                    "Inbox accessibility label 'bellWithUnreadCount' has no " +
+                        "'${Keys.InboxAccessibilityLabels.COUNT_PLACEHOLDER}' placeholder, so the " +
+                        "unread count will not be announced."
+                )
+            }
+            return NotificationInboxAccessibilityLabels(
+                bell = labels.getTypedValue<String>(Keys.InboxAccessibilityLabels.BELL),
+                bellWithUnreadCount = unreadCountTemplate?.let { template ->
+                    { count: Int ->
+                        template.replace(
+                            Keys.InboxAccessibilityLabels.COUNT_PLACEHOLDER,
+                            count.toString()
+                        )
+                    }
+                },
+                loadingIndicator = labels.getTypedValue<String>(
+                    Keys.InboxAccessibilityLabels.LOADING_INDICATOR
+                ),
+                emptyState = labels.getTypedValue<String>(
+                    Keys.InboxAccessibilityLabels.EMPTY_STATE
+                )
+            )
+        }
     }
 }
diff --git a/api-extractor-output/customerio-reactnative.api.md b/api-extractor-output/customerio-reactnative.api.md
index 5268bc39..44278cce 100644
--- a/api-extractor-output/customerio-reactnative.api.md
+++ b/api-extractor-output/customerio-reactnative.api.md
@@ -30,6 +30,7 @@ export type CioConfig = {
     autoTrackDeviceAttributes?: boolean;
     inApp?: {
         siteId: string;
+        notificationInboxAccessibilityLabels?: NotificationInboxAccessibilityLabels;
     };
     push?: {
         android?: {
@@ -351,6 +352,14 @@ export class NotificationInbox implements NotificationInboxPublicSpec {
     trackMessageClicked(message: InboxMessage, actionName?: string): void;
 }
 
+// @public
+export type NotificationInboxAccessibilityLabels = {
+    bell?: string;
+    bellWithUnreadCount?: string;
+    loadingIndicator?: string;
+    emptyState?: string;
+};
+
 // @public (undocumented)
 export const NotificationInboxBellView: React_2.FC<NotificationInboxBellViewProps>;
 
diff --git a/example/src/screens/settings.tsx b/example/src/screens/settings.tsx
index 1d362be1..0c1dd702 100644
--- a/example/src/screens/settings.tsx
+++ b/example/src/screens/settings.tsx
@@ -38,7 +38,9 @@ export const SettingsScreen = () => {
         />
         <TextField
           onChangeText={(siteId) => {
-            const inApp = { siteId: siteId };
+            // Spread the existing config so editing the site ID keeps the accessibility
+            // labels configured in the default config.
+            const inApp = { ...config.inApp, siteId: siteId };
             setConfig({ ...config, inApp });
           }}
           label="Site ID"
@@ -96,8 +98,14 @@ export const SettingsScreen = () => {
           label="Enable In-App Messaging"
           value={config.inApp?.siteId !== undefined}
           onValueChange={(enableInApp) => {
+            // Disabling clears `inApp` entirely, so re-enabling has nothing to spread
+            // and would drop the accessibility labels. Fall back to the defaults.
             const inApp = enableInApp
-              ? { siteId: config.inApp?.siteId ?? '' }
+              ? {
+                  ...Storage.instance.getDefaultCioConfig().inApp,
+                  ...config.inApp,
+                  siteId: config.inApp?.siteId ?? '',
+                }
               : undefined;
             setConfig({ ...config, inApp });
           }}
diff --git a/example/src/screens/visual-inbox.tsx b/example/src/screens/visual-inbox.tsx
index fb2ad6eb..d0c109fe 100644
--- a/example/src/screens/visual-inbox.tsx
+++ b/example/src/screens/visual-inbox.tsx
@@ -6,7 +6,7 @@ import {
   NotificationInboxView,
 } from 'customerio-reactnative';
 import React, { useEffect } from 'react';
-import { Linking, StyleSheet, Text, View } from 'react-native';
+import { Linking, Pressable, StyleSheet, Text, View } from 'react-native';
 import { showMessage } from 'react-native-flash-message';
 
 /**
@@ -94,6 +94,28 @@ export const VisualInboxScreen = ({}: NavigationScreenProps<'Visual Inbox'>) =>
           Tapping the bell opens the SDK's inbox panel — this screen presents nothing.
         </Text>
 
+        {/*
+          Debug affordance for checking the empty state. It is driven entirely by SDK data —
+          NotificationInboxView takes no props that could force it — so the only way to see the
+          dimmed-bell empty state is a profile with no messages. Identifying a fresh random user
+          gives exactly that, through the real SDK path rather than a faked view state.
+        */}
+        <Pressable
+          style={styles.debugButton}
+          onPress={() => {
+            const userId = `inbox-empty-${Date.now()}`;
+            CustomerIO.identify({ userId });
+            showMessage({
+              message: `Identified ${userId} — inbox should now be empty`,
+              type: 'info',
+            });
+          }}
+        >
+          <Text style={styles.debugButtonText}>
+            Debug: identify a fresh profile (empty inbox)
+          </Text>
+        </Pressable>
+
         {/* 2. The message list, placed inline by this screen. */}
         <Text style={styles.sectionTitle}>NotificationInboxView</Text>
         <Text style={styles.sectionBody}>
@@ -127,6 +149,14 @@ const styles = StyleSheet.create({
   // 88 not 56: the native composition insets the 56dp bell by 16 on each side, so a
   // 56-square box squeezes the circle down onto the glyph.
   bell: { width: 88, height: 88 },
+  debugButton: {
+    backgroundColor: '#e8e8ef',
+    borderRadius: 6,
+    paddingVertical: 10,
+    paddingHorizontal: 12,
+    alignItems: 'center',
+  },
+  debugButtonText: { fontSize: 13, color: '#333', fontWeight: '600' },
   embeddedList: {
     flex: 1,
     backgroundColor: '#fff',
diff --git a/example/src/services/storage.ts b/example/src/services/storage.ts
index 7267a740..a18c51b1 100644
--- a/example/src/services/storage.ts
+++ b/example/src/services/storage.ts
@@ -19,6 +19,15 @@ const createDefaultConfig = (env: Env | null | undefined): Config => {
     cdpApiKey: env?.API_KEY ?? '',
     inApp: {
       siteId: env?.SITE_ID ?? '',
+      // The SDK ships no text of its own in the visual inbox, so these are the only strings it
+      // can announce. A real app would resolve them through its own i18n so they follow the
+      // user's language; they are hardcoded here only to keep the sample self-contained.
+      notificationInboxAccessibilityLabels: {
+        bell: 'Notifications',
+        bellWithUnreadCount: 'Notifications, {count} unread',
+        loadingIndicator: 'Loading inbox',
+        emptyState: 'No notifications',
+      },
     },
     region: CioRegion.US,
     logLevel: CioLogLevel.Debug,
@@ -67,8 +76,25 @@ export class Storage {
     this.user = userJsonPayload ? JSON.parse(userJsonPayload) : null;
     // Merge persisted config over defaults so newly added default keys (e.g. the
     // geofence opt-in) are present for installs saved before those keys existed.
-    this.config = cioConfigJsonPayload
-      ? { ...Storage.defaultConfig, ...JSON.parse(cioConfigJsonPayload) }
+    const savedConfig: Config | null = cioConfigJsonPayload
+      ? JSON.parse(cioConfigJsonPayload)
+      : null;
+    this.config = savedConfig
+      ? {
+          ...Storage.defaultConfig,
+          ...savedConfig,
+          // `inApp` needs one more level of merging than the spread above gives it. A
+          // config saved before the accessibility labels existed carries only `siteId`,
+          // so a shallow spread replaces the defaults' `inApp` wholesale and silently
+          // drops them — leaving every device that ever opened Settings demonstrating
+          // the unlabeled inbox. Only merged when the saved config has `inApp` at all,
+          // so disabling in-app messaging still persists.
+          ...(savedConfig.inApp
+            ? {
+                inApp: { ...Storage.defaultConfig.inApp, ...savedConfig.inApp },
+              }
+            : {}),
+        }
       : null;
   };
 
diff --git a/jest.config.js b/jest.config.js
index 24964da9..d97f1cea 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -1,4 +1,10 @@
 module.exports = {
   testEnvironment: 'node',
   testMatch: ['<rootDir>/__tests__/**/*.test.ts'],
+  globals: {
+    // React Native defines `__DEV__` at runtime; the bare node environment does not, so any test
+    // reaching the `assert.*` parameter validation in src/utils/param-validation.ts would throw a
+    // ReferenceError instead of exercising the validation. Matches React Native's own jest preset.
+    __DEV__: true,
+  },
 };
diff --git a/package.json b/package.json
index 4f9955dd..c7cccd23 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,7 @@
     },
     "./package.json": "./package.json"
   },
-  "cioNativeiOSSdkVersion": "= 4.7.6",
+  "cioNativeiOSSdkVersion": "= 4.8.0",
   "cioiOSFirebaseWrapperSdkVersion": "= 1.0.0",
   "files": [
     "src",
diff --git a/src/types/data-pipelines.ts b/src/types/data-pipelines.ts
index 3e6fefed..c64fe5f1 100644
--- a/src/types/data-pipelines.ts
+++ b/src/types/data-pipelines.ts
@@ -1,3 +1,4 @@
+import type { NotificationInboxAccessibilityLabels } from './inbox';
 import type { LiveActivitiesConfig } from './live-activities';
 import type { PushClickBehaviorAndroid } from './push';
 
@@ -67,6 +68,11 @@ export type CioConfig = {
   autoTrackDeviceAttributes?: boolean;
   inApp?: {
     siteId: string;
+    /**
+     * Accessibility labels for the Visual Notification Inbox. Optional; an omitted label leaves
+     * that element unlabeled rather than falling back to English.
+     */
+    notificationInboxAccessibilityLabels?: NotificationInboxAccessibilityLabels;
   };
   push?: {
     android?: {
diff --git a/src/types/inbox.ts b/src/types/inbox.ts
index 03ba8c18..25a23015 100644
--- a/src/types/inbox.ts
+++ b/src/types/inbox.ts
@@ -49,3 +49,62 @@ export class InboxMessageEvent {
     this.actionValue = actionValue;
   }
 }
+
+/**
+ * Host-provided accessibility labels for the Visual Notification Inbox UI.
+ *
+ * The SDK ships no text of its own in the visual inbox — the empty state is an icon and the
+ * loading state is a spinner — so accessibility labels are the one place a string is still
+ * needed. Because the SDK cannot know your app's language, every label is optional and unset by
+ * default, and an omitted label leaves that element unlabeled rather than falling back to
+ * English. Pass strings already localized for the user's language.
+ *
+ * @example
+ * ```ts
+ * CustomerIO.initialize({
+ *   cdpApiKey: '...',
+ *   inApp: {
+ *     siteId: '...',
+ *     notificationInboxAccessibilityLabels: {
+ *       bell: t('inbox.bell'),
+ *       bellWithUnreadCount: t('inbox.unread'), // e.g. "{count} unread notifications"
+ *       loadingIndicator: t('inbox.loading'),
+ *       emptyState: t('inbox.empty'),
+ *     },
+ *   },
+ * });
+ * ```
+ *
+ * @public
+ */
+export type NotificationInboxAccessibilityLabels = {
+  /**
+   * Label for the inbox bell button. Also used when the bell shows an unread badge but
+   * `bellWithUnreadCount` is not provided. Unset → the bell is announced as an unnamed button
+   * (it stays focusable and tappable; hiding it would leave screen reader users no way in).
+   */
+  bell?: string;
+  /**
+   * Label for the bell while it shows an unread badge. Include `{count}` where the number of
+   * unread messages should appear; it is substituted at render time. Unset → falls back to `bell`.
+   *
+   * The badge itself is always hidden from assistive technologies, so the count is announced
+   * only through this label, never as bare digits appended to the button.
+   *
+   * This is a template rather than a function because configuration crosses the native bridge,
+   * which carries data but not callbacks. One template cannot express languages whose plural
+   * rules need a distinct form per count.
+   */
+  bellWithUnreadCount?: string;
+  /**
+   * Label announced for the loading spinner.
+   *
+   * Unset behaves differently per platform: on Android the spinner keeps its indeterminate
+   * progress role, which TalkBack describes in the device's own language, while on iOS it is not
+   * an accessibility element at all, so VoiceOver skips it rather than focusing an unnamed
+   * control. Set a label if you want the loading state announced on both.
+   */
+  loadingIndicator?: string;
+  /** Label announced for the empty-state icon. Unset → the icon is treated as decorative. */
+  emptyState?: string;
+};