Android how to use Environment.getExternalStorageDirectory()

Have in mind though, that getExternalStorageDirectory() is not going to work properly on some phones e.g. my Motorola razr maxx, as it has 2 cards /mnt/sdcard and /mnt/sdcard-ext - for internal and external SD cards respectfully. You will be getting the /mnt/sdcard only reply every time. Google must provide a way to deal with such a situation. As it renders many SD card aware apps (i.e card backup) failing miserably on these phones.

Environment.getExternalStorageDirectory().getAbsolutePath()

Gives you the full path the SDCard. You can then do normal File I/O operations using standard Java.

Here's a simple example for writing a file:

String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = "myFile.txt";

// Not sure if the / is on the path or not
File f = new File(baseDir + File.separator + fileName);
f.write(...);
f.flush();
f.close();

Edit:

Oops - you wanted an example for reading ...

String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = "myFile.txt";

// Not sure if the / is on the path or not
File f = new File(baseDir + File.Separator + fileName);
FileInputStream fiStream = new FileInputStream(f);

byte[] bytes;

// You might not get the whole file, lookup File I/O examples for Java
fiStream.read(bytes); 
fiStream.close();