How Should User Settings be Stored in an Android Application?

What is the best method to store user settings like saved passwords in an Android app?

// Example of saving a password in Shared Preferences
SharedPreferences sharedPreferences = getSharedPreferences("user_prefs", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("password", userPassword);
editor.apply(); // Save the changes

Storing user settings securely in an Android application is crucial for enhancing user experience while ensuring data integrity. Among various methods, Shared Preferences remain a popular choice, particularly for simple data like passwords. However, leveraging encryption or using a database might be more suitable depending on the sensitivity of the information.

// Example of using Android Keystore to encrypt a password
SecretKey secretKey = KeyStore.getInstance("AndroidKeyStore").getKey("yourKeyAlias", null);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] encryptedPassword = cipher.doFinal(userPassword.getBytes());

Causes

• Security Concerns: Passwords should be stored securely to prevent unauthorized access.
• User Convenience: Providing users with the ability to save login credentials enhances convenience.
• Data Persistence: User settings need to persist across app restarts and updates.

Solutions

• Use Shared Preferences with encryption for storing sensitive data like passwords.
• Consider using the Android Keystore system, which allows securely storing cryptographic keys and can encrypt user settings.
• For larger sets of data or more complex settings, consider using a SQLite database with proper encryption.

Mistake: Storing passwords in plain text in Shared Preferences.

Solution: Always encrypt sensitive data before storing it.

Mistake: Not using the Android Keystore for sensitive information.

Solution: Utilize the Android Keystore system for properly handling and storing cryptographic keys.