Hi I am not a complete Apple fans but I am still using iPhone 4S. Now I do really need an upgrade. I am interested in iPhone 6 (smaller version). I have a couple of questions before buying. 1. What to check about the phone when it is newly purchased at the Apple store? Local Apple sales are not very nice here. I have to know before purchase. Dead pixel ? Anything else? 2. Do I really need a dust cap for the lightning and the audio port of the iPhone? I don't mean I am going to use it in water but sometimes it's hard to avoid traces of dust or moisture during everyday's use. Could those dust cap make the world difference or if iPhone already has some extent of tolerance to dust and moisture from normal practical environment. 3. Do I need those round stuff used to protect the camera? It looks like a lot of people are talking about those little round stuff made of plastic. I don't know its name in English, but it's a kind of protector. Thank you.