Android caot execute restful url

I want to pass some parameters to a php script sitting on a webserver. The url is http://tom.byethost3.com/gcmapp/gcm.php?shareRegId=true. On the php script side, it is supposed to detect with GET that shareRegId is not null and then gather the other information via POST.A text file will then be generated. I have tested this with my MAMP server and it works. However, whenever I execute this from the app, nothing happens, I still am successful in contacting the GCM server and getting a registration ID but I can't seem to trigger the url at all.

This is the script

//Get Reg ID sent from Android App and store it in text file
if(!empty($_GET["shareRegId"])) {
    //$gcmRegID  = $_GET["shareRegId"]; 
    $gcmRegID  = $_POST["regID"]; 
    //echo $gcmRegID;
    file_put_contents("./gcmtest/GCMRegId.txt",$gcmRegID);
    echo "Done!";
    exit;
    }

This is how I send my request to the url

private void storeREG(){

    pg.show();
    params.put("regID", registerID);

    Log.d("STORE","STORE");
    //Make RESTful webservice call

    AsyncHttpClient client = new AsyncHttpClient();
    client.post(AppConstants.SERVER_URL,params,new AsyncHttpResponseHandler(){

        @Override
        public void onSuccess(String content) {
            pg.hide();
            if(pg!=null){
                pg.dismiss();
            }
            Toast.makeText(applicationCtx,"ID sharing successful",Toast.LENGTH_LONG).show();
            Intent home = new Intent(applicationCtx,HomeActivity.class);
            home.putExtra("regID",registerID);
            Log.d("REGID",registerID);
            startActivity(home);
            finish();
        }

        @Override
        public void onFailure(int statusCode, Throwable error, String content) {
            pg.hide();
            if(pg!=null){
                pg.dismiss();
            }
            Log.d("ERRORTHROW",error.toString());
            if(statusCode==404){
                Toast.makeText(applicationCtx,"Requested resource not found",Toast.LENGTH_LONG).show();
            }else if(statusCode==500){
                Toast.makeText(applicationCtx,"Something went wrong at the server",Toast.LENGTH_LONG).show();
            }else{
                Log.d("SHOWME",String.valueOf(statusCode));
                Toast.makeText(applicationCtx,"Unexpected error occurred",Toast.LENGTH_LONG).show();
            }
        }



    });

}