I do not see the usefulness of the pen, but hey, it's there. For protective films, they are fairly easy to install, especially if you use the technique of soap and water. Finally the pocket, magnet closure, the quality seems to go, I am disappointed by the metal support for the phone, it is not centered, so that the phone than on the bottom right side. Painful! The problem is that for the price, we do not find much for the ACER Z4.