I have mixed feelings about screen protectors. They do not promise your phone won't crack if you drop it, and frankly, though I carry my phone in my pocket with my keys and change and whatever else is in there, I have never really had a scratching problem. Also, getting them on just right without bubbles or dust can be very tricky. I had high hopes for the Zagg InvisibleShield Glass Screen Protector, as it had high marks at several on-line stores. The $34.99 add-on (discounted to $21.41 on Amazon) is unlike many of the lesser protectors on the market. It is made of tempered, scratch resistant glass, not plastic, and is thicker, less flexible than most. Further it claims "advanced clarity" whatever that means. The price is also higher, though if it gives you some protection and peace of mind perhaps it would be worth it. It comes with a "as long as you own the device" guarantee. They will replace the protector, but Zagg does not warrant your phone's screen won't break if you use the device.
Honestly, this is a tough sort of gizmo to test. I'm not willing to drop-test my iPhone in the name of science, particularly since if the screen breaks, but the screen protector doesn't they would consider it a success from Zagg's warranty's point of view.
So, instead I will relay my experience with it, and why it didn't stay on my phone. I followed the instructions carefully. First, I cleaned to the best of my ability the screen with the moist towelette provided. Then I used the included microfiber cloth to get off any remaining visible dust. Next, I pulled off the protective layer of the Invisible shield and, being careful not to let my fingers touch the adhesive surface, I aligned it to the phone's button and ear hole. Working from the center of the glass you press down to adhere it to the phone.
I found Zagg's shield suffers from the same pitfall as the others I've tried. Though I was careful to get off all visible dust, nevertheless they were there. This caused air bubbles to form marring the look of the screen. I tried buffing them out, but they wouldn't go away. I even tried peeling off the cover, recleaning and reapplying, but by this time the dust particles had adhered to the Zagg's adhesive, so I couldn't get them off.
It is a pity, because I found the Invisible Glass to otherwise be just that: "invisible". Unlike plastic covers that sometimes give the screen a bit of a hazy look, the Zagg product was crystal clear. Except for the air bubbles and trapped dust, that is.
