"The iPhone 4 is a device easy to work on. Since this is a simple device, that's why they block it. If you buy a car, you can do whatever you want with it. It's the same thing with your phone. It is not the phone from Apple, is the phone, "says the CEO of IFixit Kyle Wiens.
The use of Pentalobe SCREWDRIVERS in Apple iPhone 4 is a replacement of ball screws for Phillip. However, the company's strategy is to replace the screws Pentalobe with screws Phillip when a person comses repair of Apple iPhone 4.