Cross-Platform Encryption Libraries

Using well-tested encryption libraries ensures security and compatibility across platforms.
React Native Encryption Example:
// React Native - Cross-platform encryption
import CryptoJS from 'crypto-js';
import * as Keychain from 'react-native-keychain';
import AsyncStorage from '@react-native-async-storage/async-storage';

class SecureStorage {
    
    async initialize() {
        // Check if master key exists
        const hasKey = await Keychain.hasInternetCredentials('AppMasterKey');
        
        if (!hasKey) {
            // Generate new master key
            const masterKey = CryptoJS.lib.WordArray.random(256/8).toString();
            
            await Keychain.setInternetCredentials(
                'AppMasterKey',
                'master',
                masterKey,
                {
                    accessible: Keychain.ACCESSIBLE.WHEN_UNLOCKED_THIS_DEVICE_ONLY,
                    authenticatePrompt: 'Authenticate to access secure storage',
                    authenticationPromptBiometric: true
                }
            );
        }
    }
    
    async encryptAndStore(key, value) {
        try {
            // Retrieve master key
            const credentials = await Keychain.getInternetCredentials('AppMasterKey');
            const masterKey = credentials.password;
            
            // Encrypt value
            const encrypted = CryptoJS.AES.encrypt(
                JSON.stringify(value),
                masterKey
            ).toString();
            
            // Store encrypted data
            await AsyncStorage.setItem(key, encrypted);
            
            return true;
        } catch (error) {
            console.error('Encryption error:', error);
            return false;
        }
    }
    
    async retrieveAndDecrypt(key) {
        try {
            // Retrieve encrypted data
            const encrypted = await AsyncStorage.getItem(key);
            if (!encrypted) return null;
            
            // Retrieve master key
            const credentials = await Keychain.getInternetCredentials('AppMasterKey');
            const masterKey = credentials.password;
            
            // Decrypt value
            const decrypted = CryptoJS.AES.decrypt(encrypted, masterKey);
            const value = JSON.parse(decrypted.toString(CryptoJS.enc.Utf8));
            
            return value;
        } catch (error) {
            console.error('Decryption error:', error);
            return null;
        }
    }
}