Exporting data from TinyDB to CSV App Inventor

I was hoping somebody could help me or at least give me some ideas.

I am developing an App Inventor app for the engineering industry. The app is basically finished, but App Inventor does not support I/O to sd card.

Now I need to be able to get the data from the app to a pc somehow without the use of any internet connection (i.e. only over USB or WIFI)(cant use Bluetooth either)

I wrote a short Java app in Eclipse that can save some data to the sdcard, but I don't know how to launch the app from within App Inventor.

Any ideas on how I can accomplish this without having to re-write the whole app in Eclipse?

Here is the code of the Eclipse app that needs to be launched:

    package tlc.savetosd;

import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;

import android.app.Activity;
//import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.view.View.OnClickListener;

public class Savetosd extends Activity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_savetosd);     

        final EditText txtData = (EditText) findViewById(R.id.edtText);
        this.getPackageName();
        TextView txt = (TextView) findViewById(R.id.textView1);


         Button btnSave = (Button) findViewById(R.id.btnSave);
         btnSave.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
        // write on SD card file data in the text box
        try {
            File myFile = new File("/sdcard/mysdfile.txt");
            myFile.createNewFile();
            FileOutputStream fOut = new FileOutputStream(myFile);
            OutputStreamWriter myOutWriter = 
                                    new OutputStreamWriter(fOut);
            myOutWriter.append(txtData.getText());
            myOutWriter.close();
            fOut.close();
            Toast.makeText(getBaseContext(),
                    "Done writing SD 'mysdfile.txt'",
                    Toast.LENGTH_SHORT).show();
        } catch (Exception e) {
            Toast.makeText(getBaseContext(), e.getMessage(),
                    Toast.LENGTH_SHORT).show();
        }
    }// onClick
    });

}


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