Read/write file to internal private storage

I'm porting the application from Symbian/iPhone to Android, part of which is saving some data into file. I used the FileOutputStream to save the file into private folder /data/data/package_name/files:

FileOutputStream fos = iContext.openFileOutput( IDS_LIST_FILE_NAME, Context.MODE_PRIVATE ); 
fos.write( data.getBytes() ); 
fos.close();

Now I am looking for a way how to load them. I am using the FileInputStream, but it allows me to read the file byte by byte, which is pretty inefficient:

int ch;
StringBuffer fileContent = new StringBuffer("");
FileInputStream fis = iContext.openFileInput( IDS_LIST_FILE_NAME );
while( (ch = fis.read()) != -1)
  fileContent.append((char)ch);
String data = new String(fileContent);

So my question is how to read the file using better way?