Aporte original por: Chris ,
What I recommend is to remove that film and then put about 5-10 dots of black sharpie on the back of the glass where the proximity sensors go. Then wipe it off with a Q-tip or napkin and that should work. Make sure to leave some of the sharpie on. It should not show through the glass. I have this done on my white iPhone 4. Works perfect. :) Hope that helps!!