I installed the invisible shield (full version) yesterday on the iPhone 4. The kit also comes with pieces designed to go on the metal frame but they are a bit narrower than the frame. So I cut wider strips (5.8mm) to cover as much of the metal as possible without overlapping and installed these strips over the critical areas, particularly over and above the lower left corner. Since then, my death-grip-induced signal loss is over...and the "tackiness" of the invisible shield also gives me a more secure grip of the phone. I have very dry hands, so the old 3G constantly slipped out of my hands and dropped. I have reason to believe that this won't happen so easily now with the iP4. I know that we're all getting a free bumper or case, but if you want to preserve the clean look of your iP4, you may want to consider something like the above.