Does the Google speech recognizer on Android need

I use the following code to invoke the voice recognizer by google:

// This is a demonstration of Android's built in speech recognizer

package com.example.voiceinputbuiltintest;

import java.util.ArrayList;
import java.util.Locale;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.speech.RecognizerIntent;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

    private static final int VOICE_RECOGNITION = 1;
    Button speakButton ;
    TextView spokenWords; 

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        speakButton = (Button) findViewById(R.id.button1);  
        spokenWords = (TextView)findViewById(R.id.textView1);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    protected void onActivityResult(int requestCode,
            int resultCode,
            Intent data) {
        if (requestCode == VOICE_RECOGNITION && resultCode == RESULT_OK) {
            ArrayList<String> results;
            results = data.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
            // TODO Do something with the recognized voice strings

            Toast.makeText(this, results.get(0), Toast.LENGTH_SHORT).show();
            spokenWords.setText(results.get(0));
        }
        super.onActivityResult(requestCode, resultCode, data);
    }

    public void btnSpeak(View view){
        Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
        // Specify free form input
        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
        RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
        intent.putExtra(RecognizerIntent.EXTRA_PROMPT,"Please start speaking");
        intent.putExtra(RecognizerIntent.EXTRA_MAX_RESULTS, 1);
        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, Locale.ENGLISH);
        startActivityForResult(intent, VOICE_RECOGNITION);
    }


}

This works without network connection in my test machine which is Nexus 7 with Android 4.3. I thought it would work the same on any android device. However, when I try it on Samsung Galaxy S2 with Android version gingerbread.el21, the voice recogniser activity shows up, but says it needs network connection and refuses to work. Why does it work in Nexus 7 and not in Galaxy S2? Does it work offline or does it need network connection? It works in the Nexus 7 even when I stop the wifi.

In jellybean the user needs to download the offline speech recognition package.

This article sais:

Previously, when you pressed the voice icon and spoke a command or query, Android had to digitize your voice, upload it to the cloud, process the waveform, turn it into text, and send the text back down to your phone. Now the phones are powerful enough that this can be built into the device, with no extra network I/O needed. As you can imagine this results in much faster voice recognition than previous versions.

The app user will have to do this: