Run activity only once, then always run the main one

Question

As the title says, Scenario is: On first time using the app, Show Screen A. Once you are done with screen A, the button will lead to you Screen B. From now on and forever, t

Answer 1

public class FirstActivity extends Activity {

   public void onCreate(Bundle saved){
      super.onCreate();

      SharedPreferences prefs = getSharedPreferences("MyPrefs", Context.MODE_PRIVATE);

     if (!prefs.getBoolean("firstStart", true)){
          startActivity(this, SecondActivity.class);
          finish(); // Finish the current one, is like forwarding directly to the second one
      }

   }
}

Whenever you are done with showing the first activity simple set the shared prefs boolean flag to false:

prefs.getEditor.setBoolean("firstStart", false).commit();