SharedPreferences prefs = getSharedPreferences("UserData", MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
editor.putString("username", username);
editor.putString("password", password);
editor.commit();

SharedPreference prefs = getSharedPreferences("UserData", MODE_PRIVATE);
String username = prefs.getString("username","");
String pwd = prefs.getString("password","");

SharedPreferences wmbPreference1,wmbPreference2;
SharedPreferences.Editor editor;

//wmbPreference for Shared Prefs that lasts forever
wmbPreference1 = PreferenceManager.getDefaultSharedPreferences(this);

//installsp for Shared Prefs that lasts only just once each time program is running
wmbPreference2 =getApplicationContext().getSharedPreferences("install_code_prefs",Activity.MODE_PRIVATE);

SharedPreferences.Editor editor = wmbPreference1.edit();
editor.putString("MYKEY", "12345");
editor.commit();

String Phonenumber = wmbPreference1.getString("MYKEY", "");

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
String email = sharedPreferences.getString("email", null);
String password = sharedPreferences.getString("password", null");

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sharedPreferences.edit();

editor.putString("password", "helloWorld");

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("email", "helloWorld@gmail.com");
editor.putString("password", "helloWorld");
editor.commit();

private SharedPreferences prefs = null;
public static final String MY_PREFERENCE = "my_preference";// preference name
public static final String USER_NAME = "username"; // key for username
public static final String PASSWORD = "passoword";//key for password

prefs = getSharedPreferences(MY_PREFERENCE, 0);
SharedPreferences.Editor editor = prefs.edit();
        editor.putString(USER_NAME, username);
        editor.putString(PASSWORD, password);
        editor.commit();