Storing data locally is a common task for mobile applications. Such data includes preferences or authentication tokens for external services, among other things. There are many convenient solutions that allow storing data persistently, for example SQLiteDatabase, SharedPreferences, and Realm. By default these systems store the data unencrypted, thus an attacker with physical access to the device can read them out easily. Access to sensitive data can be harmful for the user of the application, for example when the device gets stolen.
