Hidden access to url

I would like to create a web counter, that counts the application activation (overall - not user specific).

In order to do that, the application should access to some url (www.mysite.com/counter). This process shouldn't be visible for the user.
I will be able to see overall number of activations in site statistics.
My questions are:

1. How to open url in the hidden form?

2. Is it legal? The counter is not user specific and doesn't not track user activities. I would like to have statistics of overall usage.

Thanks.

Use web browser control into your form and make property of web browser control i.e visible to false.
use your logic which is hidden to users and you can in background easily communicate with your www.mysite.com/counter