Flutter App Shield 🚀

Features

• Prevent Screenshots & Recordings – Black screen on Android, protected on iOS (no_screenshot)
• Blur in Background – Frosted blur overlay in app switcher (secure_application)
• Resume Authentication – Require biometrics or PIN when app returns from background
• Root/Jailbreak Detection – Block app on compromised devices
• Highly Customizable – Custom locked screens, max attempts, auto-exit, and more
• Cross-Platform – Works seamlessly on iOS and Android

Installation

Add to your pubspec.yaml:

dependencies:
  flutter_app_shield: ^0.1.4

Then run:

flutter pub get

Required Configuration

iOS – Add this to your Info.plist for biometric usage description:

<key>NSFaceIDUsageDescription</key>
<string>This app uses biometric authentication to protect your sensitive data.</string>

Android – No extra permissions needed for core features.

Usage

Just wrap your app (or any widget) with PrivacyShield:

import 'package:flutter/material.dart';
import 'package:flutter_app_shield/flutter_app_shield.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return PrivacyShield(
      preventScreenshot: true,
      requireAuthOnResume: true,
      blockOnJailbreak: true,
      blurAmount: 25.0,
      opacity: 0.9,
      maxAuthAttempts: 3,
      exitOnMaxAttempts: false,
      child: MaterialApp(
        title: 'Secure App',
        theme: ThemeData(primarySwatch: Colors.blue),
        home: const HomeScreen(),
      ),
    );
  }
}

class HomeScreen extends StatelessWidget {
  const HomeScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Secure Home')),
      body: const Center(
        child: Text('Your sensitive content is now fully protected! 🔒'),
      ),
    );
  }
}

Customization

Fully customize the security screens and behavior:

PrivacyShield(
  // ... other options
  maxAuthAttempts: 5,
  maxAttemptsMessage: 'Too many failed attempts. App locked for security.',

  // Custom warning for rooted/jailbroken devices
  compromisedDeviceBuilder: const Scaffold(
    backgroundColor: Colors.black,
    body: Center(
      child: Text(
        'This app cannot run on rooted or jailbroken devices.',
        style: TextStyle(color: Colors.red, fontSize: 20),
        textAlign: TextAlign.center,
      ),
    ),
  ),

  // Custom lock screen
  lockedBuilder: (context, controller) => Center(
    child: Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        const Icon(Icons.lock_outline, size: 80, color: Colors.white),
        const SizedBox(height: 20),
        const Text(
          'Authenticate to continue',
          style: TextStyle(color: Colors.white, fontSize: 24),
        ),
        const SizedBox(height: 30),
        ElevatedButton(
          onPressed: () => controller?.unlock(),
          child: const Text('Unlock with Biometrics'),
        ),
      ],
    ),
  ),

  child: MaterialApp(...),
);

Development & Testing

• Test screenshot prevention and root detection only on real devices
• Ensure device has biometrics or PIN set up for authentication testing
• Some features (e.g., exitOnMaxAttempts) are disabled on Flutter Web

Contributing

Contributions are very welcome! 🎉

• Report bugs or request features via Issues
• Submit Pull Requests with improvements

License

This project is licensed under the MIT License – see the LICENSE file for details.