I used a Spigen Tempered Glass Screen Protector on my wife's new 5x but it does not have cut outs for the proximity sensor. When purchased, I had never even heard of a proximitry sensor. Anyway, on my phone if this sensor is covered by a glass screen protector, the screen goes black when the phone is held to the ear (normal), but then stays black (not normal) when the phone is removed from the ear. It makes calling and receiving calls a real hassle! There are screen protectors with cut outs for the proximitry sensor. So if you're shopping for a screen protector be careful. Just a heads up.