You bought an expensive smartphone, and you don't want it to get scratched up in your purse or pocket. But do you need to add a screen protector? And can these thin pieces of plastic really help prevent cracks when you drop your phone?
It's All About The Glass
Almost all new phones these days come with enhanced glass. Whether it's Corning's Gorilla Glass or another manufacturer's version, screen glass is chemically strengthened to create a barrier against scratches. Some phone manufacturers have even hinted they don't think screen protectors do much good.
And I Don't Like Screen Protectors
Personally I am not a fan of screen protectors. Yes, they can help fight off fingerprints and reduce glare. But they are hard to apply, air bubbles get trapped under the plastic, and they don't feel as smooth to the touch as the glass. But I like scratches and cracks even less. So I'm willing to sacrifice a few phones to see how everyday and extreme exposure affects screens with and without protectors.
Keys, Coins, and a Nail File
I put a Zagg screen protector on half of a smartphone and leave the other half of the screen naked. First, I take a handful of coins and rub them vigorously across both sides of the screen. No affect on either side.
Next, I try to dig the teeth of a key into the screen. It scratches neither the naked glass nor the screen-protected side.
Finally, a nail file. Ladies, if you've ever had an Emery board escape in the bottom of your purse, you know it has a natural attraction to your sunglasses and that'll be the end of that pair. Sure enough, applying light pressure with the file to the unprotected part of the phone, scratches the screen immediately, giving an opaque ugly cloud on the otherwise crystal clear glass. But over on the screen protector side, even heavy pressure with the file seems to have little effect on the plastic film and no effect on the glass below.
Yeah, But What About a Dremel?
The screen protector fended off a manicurist's weapon, but what about a real tool: a Dremel. I've seen a demo of a screen protector that was impervious to this rotary tool, so let's get extreme.
I start on the side with the screen protector and drag the tool across the face of the phone. At the midpoint when it hits the glass, it jumps up and I can see the dust flying. Sure enough, it has etched a very prominent line across the face of the phone. As I peel back the screen protector, I'm pretty impressed; there isn't a single mark on that portion of the phone. The screen protector passes the Dremel test flawlessly.
Finally, can a screen protector really help prevent cracks in the glass or, worse, shattering if you drop your phone? I've dropped phones in torture tests before, and it's harder than it looks to crack the screen. So for this drop test, I haul out the ladder and climb 15 feet up to stand on my roof.
One iPhone 3GS has a screen protector on it and the other has no screen protector. Bombs away! Both phones land hard screen down on a tile surface. The phone without a screen protector shatters on over half the screen. The glass on the phone with a screen protector is undamaged.
So unless you carry a Dremel or a nail file at all times, the glass in current phones does a pretty good job repelling scratches. But the added drop protection that screen protectors offer may make the hassle worthwhile.