Privacy is essentially irrelevant. As long as you aren't doing something criminal the NSA/FBI/whatever don't care what they see. Unless you are a celeb, people aren't going to leak nude pics you might have sent to someone (which you shouldn't take if you don't want certain people seeing them. you assume the risk if you take them and you have to deal with the consequences). Companies can and do get plenty of data on you but just use it for targeted ads which I often find really useful actually. If you have nothing to hide, don't worry about it. Privacy issues mainly stem from someone feeling like they will be judged for what they do in my opinion.