Mjform.com

Hi There,
Im trying to find a way to add a tracking pixel or something to a new extension im making, so I can see where it is used and how popular if anything the extension is.

What would you guys recommend?

I would totally avoid that. I would just do a register sign up form before they can download it. And a compulsory field in the sign up asking which website it is going to be used on, then you can go and a look.