diff --git a/RNAmazonPublisherServices.podspec b/RNAmazonPublisherServices.podspec
index ec2c46f..4ea3314 100644
--- a/RNAmazonPublisherServices.podspec
+++ b/RNAmazonPublisherServices.podspec
@@ -17,5 +17,5 @@ Pod::Spec.new do |s|
 
   install_modules_dependencies(s)
 
-  s.dependency "AmazonPublisherServicesSDK", "5.3.1"
+  s.dependency "AmazonPublisherServicesSDK", "5.6.4"
 end
diff --git a/android/build.gradle b/android/build.gradle
index 97d45d4..d345b35 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -45,7 +45,7 @@ dependencies {
   } else {
     implementation 'com.facebook.react:react-native:+'
   }
-  implementation("com.amazon.android:aps-sdk:11.1.1")
+  implementation("com.amazon.android:aps-sdk:12.0.1")
   implementation("com.iabtcf:iabtcf-decoder:2.0.10")
 }
 
diff --git a/android/src/main/java/com/adversport/rnaps/RNAPSAdLoaderModule.java b/android/src/main/java/com/adversport/rnaps/RNAPSAdLoaderModule.java
index 65e1ffb..af0df76 100644
--- a/android/src/main/java/com/adversport/rnaps/RNAPSAdLoaderModule.java
+++ b/android/src/main/java/com/adversport/rnaps/RNAPSAdLoaderModule.java
@@ -257,7 +257,7 @@ public void loadAd(int loaderId, String adType, ReadableMap options, Promise pro
     // NOTE: options.contentUrl is intentionally ignored here.
     //
     // Amazon DSP asks for the public web URL of the content being viewed, but
-    // the Android APS SDK (com.amazon.android:aps-sdk 11.1.1) exposes no
+    // the Android APS SDK (com.amazon.android:aps-sdk 12.0.1) exposes no
     // equivalent of the iOS +[APS setContentUrl:] — verified by inspecting every
     // public member of AdRegistration and DTBAdRequest. There is no supported
     // way to attach it to an Android bid request today.
diff --git a/android/src/main/java/com/adversport/rnaps/RNAPSAdsModule.java b/android/src/main/java/com/adversport/rnaps/RNAPSAdsModule.java
index e14ee68..9c7b208 100644
--- a/android/src/main/java/com/adversport/rnaps/RNAPSAdsModule.java
+++ b/android/src/main/java/com/adversport/rnaps/RNAPSAdsModule.java
@@ -18,6 +18,7 @@
  * along with Foobar. If not, see <https://www.gnu.org/licenses/>.
  */
 
+import com.amazon.aps.ads.common.ApsExternalUserId;
 import com.amazon.device.ads.AdRegistration;
 import com.amazon.device.ads.DTBAdNetwork;
 import com.amazon.device.ads.DTBAdNetworkInfo;
@@ -25,6 +26,9 @@
 import com.facebook.react.bridge.*;
 import com.facebook.react.module.annotations.ReactModule;
 import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 @ReactModule(name = RNAPSAdsModule.MODULE_NAME)
 public class RNAPSAdsModule extends ReactContextBaseJavaModule {
@@ -153,4 +157,72 @@ public void addCustomAttribute(String key, String value) {
   public void removeCustomAttribute(String key) {
     AdRegistration.removeCustomAttribute(key);
   }
+
+  /**
+   * Third-party identifiers (ID5, LiveRamp...), forwarded by Amazon to the TAM/UAM bidders the
+   * publisher has enabled. Set once per user session; call again when an id changes. Passing an
+   * empty array clears them, which is what a consent withdrawal must do.
+   */
+  @ReactMethod
+  public void setExternalUserIds(ReadableArray externalUserIds) {
+    List<ApsExternalUserId> ids = new ArrayList<>();
+
+    for (int i = 0; i < externalUserIds.size(); i++) {
+      ReadableMap entry = externalUserIds.getMap(i);
+      if (entry == null || !entry.hasKey("source")) {
+        continue;
+      }
+      String source = entry.getString("source");
+      ReadableArray uids = entry.hasKey("uids") ? entry.getArray("uids") : null;
+      if (source == null || uids == null || uids.size() == 0) {
+        continue;
+      }
+
+      ApsExternalUserId.Builder builder = ApsExternalUserId.Companion.builder().addSource(source);
+      boolean hasUid = false;
+
+      for (int j = 0; j < uids.size(); j++) {
+        ReadableMap uid = uids.getMap(j);
+        if (uid == null || !uid.hasKey("id")) {
+          continue;
+        }
+        String id = uid.getString("id");
+        if (id == null) {
+          continue;
+        }
+        Integer atype = uid.hasKey("atype") ? uid.getInt("atype") : null;
+        builder.addUniqueId(id, atype, readStringMap(uid, "ext"));
+        hasUid = true;
+      }
+
+      if (hasUid) {
+        ids.add(builder.build());
+      }
+    }
+
+    AdRegistration.setExternalUserIds(ids);
+  }
+
+  /**
+   * Reads a nested string map, skipping any non-string value rather than failing the whole call.
+   */
+  private static Map<String, String> readStringMap(ReadableMap parent, String key) {
+    if (!parent.hasKey(key)) {
+      return null;
+    }
+    ReadableMap map = parent.getMap(key);
+    if (map == null) {
+      return null;
+    }
+    Map<String, String> out = new HashMap<>();
+    ReadableMapKeySetIterator iterator = map.keySetIterator();
+    while (iterator.hasNextKey()) {
+      String k = iterator.nextKey();
+      String v = map.getString(k);
+      if (v != null) {
+        out.put(k, v);
+      }
+    }
+    return out.isEmpty() ? null : out;
+  }
 }
diff --git a/ios/RNAPS/RNAPSAdsModule.m b/ios/RNAPS/RNAPSAdsModule.m
index 3b37408..b3f37af 100644
--- a/ios/RNAPS/RNAPSAdsModule.m
+++ b/ios/RNAPS/RNAPSAdsModule.m
@@ -39,4 +39,6 @@ @interface RCT_EXTERN_MODULE (RNAPSAdsModule, NSObject)
 
 RCT_EXTERN_METHOD(removeCustomAttribute : (nonnull NSString *)key)
 
+RCT_EXTERN_METHOD(setExternalUserIds : (nonnull NSArray *)externalUserIds)
+
 @end
diff --git a/ios/RNAPS/RNAPSAdsModule.swift b/ios/RNAPS/RNAPSAdsModule.swift
index c195224..9ae2f09 100644
--- a/ios/RNAPS/RNAPSAdsModule.swift
+++ b/ios/RNAPS/RNAPSAdsModule.swift
@@ -98,6 +98,18 @@ class RNAPSAdsModule: NSObject {
     DTBAds.sharedInstance().testMode = enabled
   }
 
+  // The setters below still go through the deprecated DTBAds singleton on purpose.
+  //
+  // Their replacements are not setters at all: APS 5.6.4 moved testMode, useGeolocation,
+  // mraidPolicy and mraidSupportedVersions onto APSInitConfig, an object handed once to
+  // +[APS initializeWithAppKey:config:completion:]. Adopting them means reshaping this
+  // bridge's contract — JS calls initialize() first and these setters afterwards, which
+  // the config model cannot express — so it belongs in its own change, not here.
+  //
+  // Do not trust the deprecation text: it points at +[APS setTestMode:] and friends, which
+  // are declared nowhere in APS.h (the selectors do exist in the binary). Read APSInitConfig.h.
+  //
+  // removeCustomAttribute has no replacement at all, on APS or on APSInitConfig.
   @objc(setUseGeoLocation:)
   func setUseGeoLocation(enabled: Bool) -> Void {
     DTBAds.sharedInstance().useGeoLocation = enabled
@@ -105,7 +117,7 @@ class RNAPSAdsModule: NSObject {
 
   @objc(addCustomAttribute:value:)
   func addCustomAttribute(key: String, value: String) {
-    DTBAds.sharedInstance().addCustomAttribute(key, value: value)
+    APS.setCustomAttribute(value, forKey: key)
   }
 
   @objc(removeCustomAttribute:)
@@ -113,4 +125,26 @@ class RNAPSAdsModule: NSObject {
     DTBAds.sharedInstance().removeCustomAttribute(key)
   }
 
+  // Third-party identifiers (ID5, LiveRamp...), forwarded by Amazon to the TAM/UAM bidders
+  // the publisher has enabled. Set once per user session; call again when an id changes.
+  // Passing an empty array clears them, which is what a consent withdrawal must do.
+  @objc(setExternalUserIds:)
+  func setExternalUserIds(externalUserIds: [[String: Any]]) {
+    let ids: [APSExternalUserId] = externalUserIds.compactMap { entry in
+      guard let source = entry["source"] as? String,
+            let uids = entry["uids"] as? [[String: Any]], !uids.isEmpty else {
+        return nil
+      }
+      // Swift imports the +builder factory as an initializer, so `.builder()` does not exist here.
+      let builder = APSExternalUserIdBuilder()
+      _ = builder.addSource(source)
+      for uid in uids {
+        guard let id = uid["id"] as? String else { continue }
+        _ = builder.addUniqueId(id, atype: uid["atype"] as? NSNumber, ext: uid["ext"] as? [String: String])
+      }
+      return builder.build()
+    }
+    APS.setExternalUserIds(ids)
+  }
+
 }
diff --git a/package.json b/package.json
index 50e4f14..27b77ad 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "react-native-aps",
   "packageManager": "yarn@4.3.1",
-  "version": "2.3.0",
+  "version": "2.4.0",
   "author": "AdversportTeam <rm@adversport.com> (https://github.com/AdversportTeam)",
   "contributors": [
     "Jay Kim <me@wjay.kim> (https://github.com/wjaykim)"
diff --git a/src/APSAds.ts b/src/APSAds.ts
index 77f668d..a94c2a5 100644
--- a/src/APSAds.ts
+++ b/src/APSAds.ts
@@ -22,6 +22,10 @@ import {
   validateAdNetworkInfo,
 } from './types/AdNetworkInfo';
 import { isMRAIDPolicy, MRAIDPolicy } from './types/MRAIDPolicy';
+import {
+  type ExternalUserId,
+  validateExternalUserIds,
+} from './types/ExternalUserId';
 
 export class APSAds {
   private static _nativeModule = AdsModule;
@@ -129,4 +133,22 @@ export class APSAds {
     }
     return this._nativeModule.removeCustomAttribute(key);
   }
+
+  /**
+   * Sets the third-party user identifiers (ID5, LiveRamp...) sent with every bid request.
+   * Amazon forwards them to the TAM/UAM bidders the publisher has enabled.
+   *
+   * Set once per user session, and call again whenever an id changes. Pass an empty array to
+   * clear them, which is what a consent withdrawal must do.
+   */
+  static setExternalUserIds(externalUserIds: ExternalUserId[]): void {
+    try {
+      validateExternalUserIds(externalUserIds);
+    } catch (e) {
+      if (e instanceof Error) {
+        throw new Error(`APSAds.setExternalUserIds(*) ${e.message}`);
+      }
+    }
+    return this._nativeModule.setExternalUserIds(externalUserIds);
+  }
 }
diff --git a/src/__tests__/APSAds.test.ts b/src/__tests__/APSAds.test.ts
index 4b2995a..431456e 100644
--- a/src/__tests__/APSAds.test.ts
+++ b/src/__tests__/APSAds.test.ts
@@ -1,4 +1,5 @@
 import { APSAds } from '../APSAds';
+import AdsModule from '../internal/AdsModule';
 import { AdNetwork, MRAIDPolicy } from '../types';
 
 jest.mock('../internal/AdsModule');
@@ -108,6 +109,53 @@ describe('APSAds', function () {
       expect(APSAds.addCustomAttribute('key', 'value')).toBeUndefined();
     });
   });
+  describe('setExternalUserIds', function () {
+    const anId5Eid = {
+      source: 'id5-sync.com',
+      uids: [{ id: 'ID5*abc', atype: 2, ext: { linkType: '2' } }],
+    };
+
+    it('throws if externalUserIds is not an array', function () {
+      // @ts-ignore
+      expect(() => APSAds.setExternalUserIds('nope')).toThrowError(
+        "APSAds.setExternalUserIds(*) 'externalUserIds' expected an array value"
+      );
+    });
+    it('throws if source is missing', function () {
+      expect(() =>
+        // @ts-ignore
+        APSAds.setExternalUserIds([{ uids: [{ id: 'a' }] }])
+      ).toThrowError(
+        "APSAds.setExternalUserIds(*) 'externalUserIds[0].source' expected a string value"
+      );
+    });
+    it('throws if uids is empty', function () {
+      expect(() =>
+        APSAds.setExternalUserIds([{ source: 'id5-sync.com', uids: [] }])
+      ).toThrowError(
+        "APSAds.setExternalUserIds(*) 'externalUserIds[0].uids' expected a non-empty array value"
+      );
+    });
+    it('throws if a uid has no id', function () {
+      expect(() =>
+        APSAds.setExternalUserIds([
+          // @ts-ignore
+          { source: 'id5-sync.com', uids: [{ atype: 2 }] },
+        ])
+      ).toThrowError(
+        "APSAds.setExternalUserIds(*) 'externalUserIds[0].uids[0].id' expected a string value"
+      );
+    });
+    it('accepts an eid as returned by the issuer, untouched', function () {
+      expect(APSAds.setExternalUserIds([anId5Eid])).toBeUndefined();
+      expect(AdsModule.setExternalUserIds).toHaveBeenCalledWith([anId5Eid]);
+    });
+    it('accepts an empty array, which clears the ids', function () {
+      expect(APSAds.setExternalUserIds([])).toBeUndefined();
+      expect(AdsModule.setExternalUserIds).toHaveBeenCalledWith([]);
+    });
+  });
+
   describe('removeCustomAttribute', function () {
     it('throws if key is invalid', function () {
       // @ts-ignore
diff --git a/src/internal/__mocks__/AdsModule.ts b/src/internal/__mocks__/AdsModule.ts
index 577ecf0..205ed84 100644
--- a/src/internal/__mocks__/AdsModule.ts
+++ b/src/internal/__mocks__/AdsModule.ts
@@ -7,6 +7,7 @@ const AdsModule = {
   setUseGeoLocation: jest.fn(),
   addCustomAttribute: jest.fn(),
   removeCustomAttribute: jest.fn(),
+  setExternalUserIds: jest.fn(),
 };
 
 export default AdsModule;
diff --git a/src/turbomodules/NativeRNAPSAdsModule.ts b/src/turbomodules/NativeRNAPSAdsModule.ts
index bbcbf61..98808a9 100644
--- a/src/turbomodules/NativeRNAPSAdsModule.ts
+++ b/src/turbomodules/NativeRNAPSAdsModule.ts
@@ -45,6 +45,8 @@ export interface Spec extends TurboModule {
   addCustomAttribute: (key: string, value: string) => void;
 
   removeCustomAttribute: (key: string) => void;
+
+  setExternalUserIds: (externalUserIds: Object[]) => void;
 }
 
 export default TurboModuleRegistry.getEnforcing<Spec>('RNAPSAdsModule');
diff --git a/src/types/ExternalUserId.ts b/src/types/ExternalUserId.ts
new file mode 100644
index 0000000..0633126
--- /dev/null
+++ b/src/types/ExternalUserId.ts
@@ -0,0 +1,44 @@
+/**
+ * A third-party user identifier, in the OpenRTB `user.eids` shape.
+ *
+ * Amazon forwards these to the TAM/UAM bidders the publisher has enabled. The object is
+ * meant to be passed through untouched from whoever issued it (ID5, LiveRamp...): `atype`
+ * and `ext` are opaque to us and must not be rebuilt.
+ *
+ * @see https://resources.ams.amazon.com/s/article/external-user-ids
+ */
+export interface ExternalUserId {
+  /** Identifier domain, e.g. `id5-sync.com`. */
+  source: string;
+  uids: Array<{
+    id: string;
+    /** OpenRTB agent type. 1 = probabilistic, 2 = device advertising id. */
+    atype?: number;
+    ext?: Record<string, string>;
+  }>;
+}
+
+export function validateExternalUserIds(externalUserIds: ExternalUserId[]) {
+  if (!Array.isArray(externalUserIds)) {
+    throw new Error("'externalUserIds' expected an array value");
+  }
+  externalUserIds.forEach((externalUserId, index) => {
+    if (typeof externalUserId?.source !== 'string') {
+      throw new Error(
+        `'externalUserIds[${index}].source' expected a string value`
+      );
+    }
+    if (!Array.isArray(externalUserId.uids) || !externalUserId.uids.length) {
+      throw new Error(
+        `'externalUserIds[${index}].uids' expected a non-empty array value`
+      );
+    }
+    externalUserId.uids.forEach((uid, uidIndex) => {
+      if (typeof uid?.id !== 'string') {
+        throw new Error(
+          `'externalUserIds[${index}].uids[${uidIndex}].id' expected a string value`
+        );
+      }
+    });
+  });
+}
diff --git a/src/types/index.ts b/src/types/index.ts
index 6841042..b1045cd 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -23,3 +23,4 @@ export { AdNetwork } from './AdNetwork';
 export type { AdNetworkInfo } from './AdNetworkInfo';
 export { AdType } from './AdType';
 export { MRAIDPolicy } from './MRAIDPolicy';
+export * from './ExternalUserId';