code: protected static InputStream getConfigurationFileFromSDCard(String fileName) {
          File sdcard = Environment.getExternalStorageDirectory();
          if (sdcard == null || !sdcard.exists() || !sdcard.canRead()) {
              return null;
          }
  
          String sdCardPath = sdcard.getAbsolutePath();
  
          File propFile = new File(sdCardPath + "/" + fileName);
          if (!propFile.exists()) {
              return null;
          }
  
          FileInputStream fileIs = null;
          try {
              fileIs = new FileInputStream(propFile);
          } catch (FileNotFoundException e) {
              // should not happen, we check that above
              return null;
          }
  
          return fileIs;
      }
docs: Gets an input on a configuration file placed on the the SDCard.
  
  @param fileName
  the file name
  @return the input stream to read the file or <code>null</code> if the
  file does not exist.