Tnie is my fourth phone. All previous had the same problem, this too... When you're turning on the phone, on startscreen appear a small flashing point for a second and always in different parts of the screen - only when turning on. To see it, you have to focus and stare at startscreen( black with apple in the middle) preferably in a dark room. What the hell is it? Did you guys have the same problem? This is the fourth iphone4 with this!!