The BodyGuardz Protective Skin for iPhone 4 provides excellent scratch protection
Application can be a little daunting, but if you take a gander at the video above we'll walk you through the steps. I find the trick is to not be shy about using the supplied spray so you can more easily adjust the screen protector and squeeze out those bubbles. It's also worth noting that for at least a day after you apply it and sometimes a few days, your iPhone 4 is going to look a little weird - but having used these products for many years I know that the bubbles and 'fog' goes away completely.
After the break, a few more thoughts, a small gallery of photos, and a video showing how to apply the protective skin.
Once on, the iPhone isn't any thicker, of course, and the glass on both the front and back are completely protected from scratches. The rear-skin is open so as not to occlude the camera lens, but that tiny extra thickness also means the lens isn't resting on a table when you set it down, which I also like.
This particular skin has a glossy rather than a matted finish, but it also adds just a bit of extra grip to the sides and back, which I appreciate. I'll note too that my iPhone definitely suffers from a fairly serious "Hold Different" Death Grip signal issue and the BodyGuards doesn't attenuate it. If you're looking to fix that, you'll want to get an iPhone 4 case instead of (or in addition to) the BodyGuardz
So while application is a hassle (they include two full skins in the box), once you have it on your iPhone the knowledge that it's protected from keys, grit, and other causes of scratches is indeed a balm.
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