How to Redirect from One Flutter App to Another Flutter App and Navigate Back

In many real-world mobile applications, you may need to open another Flutter app from your Flutter app and then return back to the original app. This is common in scenarios like:

• Payment apps (open UPI / wallet app)
• Authentication apps
• Partner apps integration
• Deep linking between multiple company apps

In this complete guide, you will learn:

✅ How to open another Flutter app
✅ How to pass data between apps
✅ How to return back to the first app
✅ How to handle Android & iOS
✅ Best practices and common issues

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1. Concepts You Must Know

To redirect between two Flutter apps, you mainly use:

• URL Schemes (iOS & Android)
• Android Intents
• Deep Linking
• Universal Links (iOS)
• App Links (Android)

Flutter provides plugins to make this easy:

• url_launcher
• uni_links
• app_links

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2. Use Case Example

We will assume:

• App A (Sender App) → Opens App B
• App B (Receiver App) → Does some work → Returns back to App A

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3. Step 1: Setup Deep Linking in App B (Receiver App)

App B must expose a custom URL scheme so App A can open it.

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Android Setup (App B)

Edit android/app/src/main/AndroidManifest.xml

<activity
    android:name=".MainActivity"
    android:launchMode="singleTask"
    android:exported="true">

    <intent-filter>
        <action android:name="android.intent.action.VIEW"/>
        <category android:name="android.intent.category.DEFAULT"/>
        <category android:name="android.intent.category.BROWSABLE"/>

        <!-- Custom Scheme -->
        <data
            android:scheme="appb"
            android:host="open"/>
    </intent-filter>
</activity>

This creates a link like:

appb://open

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iOS Setup (App B)

Edit ios/Runner/Info.plist

<key>CFBundleURLTypes</key>
<array>
  <dict>
    <key>CFBundleURLSchemes</key>
    <array>
      <string>appb</string>
    </array>
  </dict>
</array>

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4. Step 2: Open App B from App A

Install plugin in App A:

dependencies:
  url_launcher: ^6.2.4

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Flutter Code (App A)

import 'package:url_launcher/url_launcher.dart';

Future<void> openAppB() async {
  final Uri uri = Uri.parse('appb://open?from=appA&userId=123');

  if (await canLaunchUrl(uri)) {
    await launchUrl(uri, mode: LaunchMode.externalApplication);
  } else {
    throw 'Could not open App B';
  }
}

This will:

✅ Open App B
✅ Pass parameters (from, userId)

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5. Step 3: Receive Data in App B

Use uni_links to listen for incoming deep links.

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Install in App B

dependencies:
  uni_links: ^0.5.1

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Handle Incoming Link in App B

import 'package:uni_links/uni_links.dart';

void initDeepLinks() {
  uriLinkStream.listen((Uri? uri) {
    if (uri != null) {
      final from = uri.queryParameters['from'];
      final userId = uri.queryParameters['userId'];

      print('Opened from: $from');
      print('UserId: $userId');
    }
  });
}

Call initDeepLinks() in initState().

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6. Step 4: Return Back to App A from App B

Now App A must also support deep links.

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Setup Deep Link in App A

Use a scheme for App A:

appa://open

AndroidManifest.xml (App A)

<intent-filter>
    <action android:name="android.intent.action.VIEW"/>
    <category android:name="android.intent.category.DEFAULT"/>
    <category android:name="android.intent.category.BROWSABLE"/>

    <data
        android:scheme="appa"
        android:host="open"/>
</intent-filter>

Info.plist (App A)

<key>CFBundleURLTypes</key>
<array>
  <dict>
    <key>CFBundleURLSchemes</key>
    <array>
      <string>appa</string>
    </array>
  </dict>
</array>

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Flutter Code (App B → Back to App A)

Future<void> returnToAppA() async {
  final Uri uri = Uri.parse('appa://open?status=success&txId=999');

  if (await canLaunchUrl(uri)) {
    await launchUrl(uri, mode: LaunchMode.externalApplication);
  }
}

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7. Handle Return Data in App A

void initDeepLinks() {
  uriLinkStream.listen((Uri? uri) {
    if (uri != null) {
      final status = uri.queryParameters['status'];
      final txId = uri.queryParameters['txId'];

      print('Status: $status');
      print('Transaction ID: $txId');
    }
  });
}

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8. Flow Diagram (High Level)

App A  --->  appb://open  --->  App B
App B  --->  appa://open  --->  App A

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9. Best Practices

✅ Use unique URL schemes
✅ Always validate incoming parameters
✅ Handle app not installed case (redirect to Play Store / App Store)
✅ Use App Links / Universal Links for production
✅ Secure sensitive data (don’t pass tokens in URL)

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10. Common Issues & Fixes

Problem	Solution
App not opening	Check scheme & host
iOS not working	Add URL Types in Info.plist
Android opens browser	Fix intent-filter
App opens but no data	Check uni_links listener
Multiple instances	Use launchMode=”singleTask”

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11. Advanced (Recommended for Production)

For large apps, use:

• Android App Links
• iOS Universal Links
• Firebase Dynamic Links

These are more secure and reliable than custom schemes.

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Conclusion

Redirecting between two Flutter apps is very useful for:

• Payments
• Authentication
• Partner integrations
• Modular app ecosystems

By using deep links + url_launcher + uni_links, you can easily:

✅ Open another Flutter app
✅ Pass data
✅ Return back with result