AFAIK mobile app sends license key along with IMEI or other stuff to SlideMe server and it sends back if that device has bought it(not user)
However, the creation of license key is completely depend on developers and that can be same as any other developer's key. There are some chances of it happening. Now wouldn't it be nice and more accurate, if SlideMe site generates the key on website when adding first step of uploading application. Later you can add binary files then publish.