Question

I am new to android development and i want to implement an external storage on SD card so as to store username for particular application.

Answer 1

To store username, you just need to implement SharedPreferences, also check this article.

For example:

Storing time:

SharedPreferences myPrefs = this.getSharedPreferences("myPrefs", MODE_WORLD_READABLE);
        SharedPreferences.Editor prefsEditor = myPrefs.edit();
        prefsEditor.putString("username, "pareshmayani");
        prefsEditor.commit();

Retrieval Time:

 SharedPreferences myPrefs = this.getSharedPreferences("myPrefs", MODE_WORLD_READABLE);
 String prefName = myPrefs.getString("username", null);