That's why you turn that **** off on your smartphone options....I think the bigger problem would be some sort of a data base as to who has what over what is and isn't stolen. Something to keep in mind is that pictures taken with phones have data with them like time date and location. A lot of pictures are automatically loaded to a server somewhere. So lets say you take a pic and color over the serial number and post that pic, the original pic is probably already stored somewhere else with out the number covered. So while people that you are selling to can't see it whoever is in charge of the servers could. It's a long stretch but this day in age not a hard one