/// <summary>
        /// Gets value from the AndroidKeyStore
        /// </summary>
        /// <param name="key"></param>
        /// <param name="defaultValue"></param>
        /// <returns></returns>
        public string GetValue(string key, string defaultValue = null)
        {
            string encStr;

            using (var prefs = AppContext.GetSharedPreferences(SecurePreferenceName, FileCreationMode.Private))
                encStr = prefs.GetString(GetMD5Hash(key), defaultValue);

            string decryptedData = null;

            if (!string.IsNullOrEmpty(encStr))
            {
                var encData = Convert.FromBase64String(encStr);
                var ks      = new AndroidKeyStore(AppContext, SecurePreferenceName);
                decryptedData = ks.Decrypt(encData);

                return(decryptedData);
            }

            return(defaultValue);
        }