diff --git a/ios/ExpoIap.podspec b/ios/ExpoIap.podspec
index eb1fb0578..fcf599f54 100644
--- a/ios/ExpoIap.podspec
+++ b/ios/ExpoIap.podspec
@@ -26,7 +26,14 @@ Pod::Spec.new do |s|
   s.dependency 'ExpoModulesCore'
   s.dependency 'openiap', "#{versions['apple']}"
 
-  # OnsideKit is optional; added via ensureOnsidePod() in Podfile when modules.onside is enabled
+  # OnsideKit is optional; only included when modules.onside is enabled via the Expo plugin.
+  # The plugin adds `pod 'ExpoIap/Onside'` to the Podfile when onside is enabled.
+  s.subspec 'Onside' do |ss|
+    ss.dependency 'OnsideKit'
+  end
+
+  s.default_subspecs = []
+
   # Swift/Objective-C compatibility
   s.pod_target_xcconfig = {
     'DEFINES_MODULE' => 'YES',
diff --git a/plugin/__tests__/withIAP.test.ts b/plugin/__tests__/withIAP.test.ts
index 976885164..f903540b0 100644
--- a/plugin/__tests__/withIAP.test.ts
+++ b/plugin/__tests__/withIAP.test.ts
@@ -1,6 +1,7 @@
 import type {ExpoConfig} from '@expo/config-types';
 import {
   computeAutolinkModules,
+  ensureOnsidePodIOS,
   modifyAppBuildGradle,
   resolveModuleSelection,
 } from '../src/withIAP';
@@ -28,7 +29,7 @@ jest.mock('expo/config-plugins', () => {
 
   return {
     ...plugins,
-    WarningAggregator: {addWarningAndroid: jest.fn()},
+    WarningAggregator: {addWarningAndroid: jest.fn(), addWarningIOS: jest.fn()},
   };
 });
 
@@ -183,3 +184,68 @@ describe('ios module selection', () => {
     });
   });
 });
+
+describe('ensureOnsidePodIOS', () => {
+  const basePodfile = [
+    "source 'https://cdn.cocoapods.org/'",
+    '',
+    "target 'MyApp' do",
+    "  pod 'ExpoModulesCore'",
+    'end',
+    '',
+  ].join('\n');
+
+  it('adds ExpoIap/Onside subspec pod', () => {
+    const result = ensureOnsidePodIOS(basePodfile);
+    expect(result).toContain("pod 'ExpoIap/Onside'");
+  });
+
+  it('inserts pod inside the target block', () => {
+    const result = ensureOnsidePodIOS(basePodfile);
+    const targetIndex = result.indexOf("target 'MyApp' do");
+    const subspecIndex = result.indexOf("pod 'ExpoIap/Onside'");
+    const endIndex = result.indexOf('end');
+    expect(subspecIndex).toBeGreaterThan(targetIndex);
+    expect(subspecIndex).toBeLessThan(endIndex);
+  });
+
+  it('skips if ExpoIap/Onside already exists', () => {
+    const podfileWithSubspec = [
+      "target 'MyApp' do",
+      "  pod 'ExpoIap/Onside', :path => '../node_modules/expo-iap/ios'",
+      'end',
+    ].join('\n');
+    const result = ensureOnsidePodIOS(podfileWithSubspec);
+    expect(result).toBe(podfileWithSubspec);
+  });
+
+  it('returns unchanged content when no target block found', () => {
+    const noPodfile = '# empty';
+    const result = ensureOnsidePodIOS(noPodfile);
+    expect(result).toBe(noPodfile);
+  });
+
+  it('does not modify Podfile when onside is disabled (not called)', () => {
+    const enableOnside = false;
+    let content = basePodfile;
+
+    if (enableOnside) {
+      content = ensureOnsidePodIOS(content);
+    }
+
+    expect(content).toBe(basePodfile);
+    expect(content).not.toContain("pod 'ExpoIap/Onside'");
+  });
+
+  it('modifies Podfile when onside is enabled', () => {
+    const enableOnside = true;
+    let content = basePodfile;
+
+    if (enableOnside) {
+      content = ensureOnsidePodIOS(content);
+    }
+
+    expect(content).not.toBe(basePodfile);
+    expect(content).toContain("pod 'ExpoIap/Onside'");
+  });
+});
diff --git a/plugin/src/withIAP.ts b/plugin/src/withIAP.ts
index c52df44dd..716d280e0 100644
--- a/plugin/src/withIAP.ts
+++ b/plugin/src/withIAP.ts
@@ -7,7 +7,6 @@ import {
   withGradleProperties,
   withInfoPlist,
   withPodfile,
-  withAppDelegate,
 } from 'expo/config-plugins';
 import type {ExpoConfig} from '@expo/config-types';
 import * as fs from 'fs';
@@ -263,12 +262,10 @@ const withIapAndroid: ConfigPlugin<
   return config;
 };
 
-const ensureOnsidePod = (content: string): string => {
-  const podLine =
-    "  pod 'OnsideKit', :podspec => 'https://raw.githubusercontent.com/onside-io/OnsideKit-iOS/0.5.0/OnsideKit.podspec'";
-  const podRegex = /^\s*pod\s+'OnsideKit'\b.*$/m;
+const EXPO_IAP_IOS_PATH = '../node_modules/expo-iap/ios';
 
-  if (podRegex.test(content)) {
+export const ensureOnsidePodIOS = (content: string): string => {
+  if (/^\s*pod\s+['"]ExpoIap\/Onside['"].*$/m.test(content)) {
     return content;
   }
 
@@ -276,18 +273,17 @@ const ensureOnsidePod = (content: string): string => {
   if (!targetMatch) {
     WarningAggregator.addWarningIOS(
       'expo-iap',
-      'Could not find a target block in Podfile when adding OnsideKit; skipping installation.',
+      'Could not find a target block in Podfile when adding ExpoIap/Onside; skipping installation.',
     );
     return content;
   }
 
+  const podLine = `  pod 'ExpoIap/Onside', :path => '${EXPO_IAP_IOS_PATH}'\n`;
   const insertIndex = targetMatch.index! + targetMatch[0].length;
-  const before = content.slice(0, insertIndex);
-  const after = content.slice(insertIndex);
 
-  logOnce('📦 expo-iap: Added OnsideKit pod to Podfile');
+  logOnce('📦 expo-iap: Added ExpoIap/Onside subspec to Podfile');
 
-  return `${before}${podLine}\n${after}`;
+  return content.slice(0, insertIndex) + podLine + content.slice(insertIndex);
 };
 
 export type AutolinkState = {expoIap: boolean; onside: boolean};
@@ -493,7 +489,7 @@ const withIapIOS: ConfigPlugin<WithIapIosOptions | undefined> = (
 
     // 3) Optionally install OnsideKit when enabled in config
     if (options?.enableOnside) {
-      content = ensureOnsidePod(content);
+      content = ensureOnsidePodIOS(content);
     }
 
     config.modResults.contents = content;