Here is demo for creating text file and append text to that file in JAVA. For this in Android you have to ask for WRITE_EXTERNAL_STORAGE permission. you can check this : if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { if (ContextCompat.checkSelfPermission(getBaseContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, WRITE_STORAGE_INT); return; } } Please handle this request in onRequestPermissionsResult.   Finally actual code to write text file in java is :  try{ […]