Recently, I installed the ZAGG invisibleSHIELD on my Verizon iPhone 4 (both the front and back protectors). I've been using it on my phone for about a week and a half now, and am able to provide a good review of the shields after some usage.
ZAGG invisibleSHIELD's allow for a "wet install," or one where you use a solution that you spray on the shield. This allows you to set the shield on the device, but still move it around for a bit to position it to your liking. From previous experiences, I can definitely say that this install was one of the easiest ones. Again, because of the wet install, you can move the shield around to position is perfectly, and air bubbles can be squeegeed out afterwards.
With that being said, don't install the shields if you don't have a good hour and a half of free time, because it's going to take time to get all the solution out using the squeegee. After installation, ZAGG recommends you leave the device off for 24 hours, but this isn't needed. Also, we don't recommend putting any case on the device for at least 48 hours after installation of the shields.
How's it cut?
Surprisingly, the shield was cut relatively well. The edges of the shield (both front and back) match up relatively well with the edge of the iPhone. There is some abnormality with the cut around the home button, even if you position the shield near perfect. Also, the cut around the earpiece on the iPhone is a little rough when you hold the phone to your face - be aware of this.
The camera+flash cut out on the back is near perfect, but some dust does get underneath the shield after time - be aware of this too.
How has the shield on the back of the iPhone lasted?
After a week and a half of usage, I began to notice small scratches on the shield that's installed on the back of the iPhone 4. These scratches appeared even though ZAGG claims that these shields are virtually un-scratchable - this claim isn't very accurate as you can see. Also after a week and a half, I noticed a lot of dust piling up on the edge of the iPhone, and it's pretty hard to clean it off because the dust is underneath the shield.
Also, the protector is a fingerprint magnet - you're probably going to want to clean it off every few days.
How has the shield on the front of the iPhone lasted?
After a week and a half of usage, the screen protector has a few small scratches on it (just like the one of the back). Also just like the back one, the screen protector is a fingerprint magnet - you're probably going to want to clean this one off every day or so to keep it clean.
As you see in some of the pictures, the front shield has a very distinct texture and look to it. It isn't a "crystal," or clean, shield and doesn't have a very smooth texture to the touch. With that being said, the texture on the protector is nice for many things, just not something that involves a lot of scrolling. When the device's screen is on, you're not going to see that bubbly look on the protector.
Also, as a few pictures show, in the top-left corner of the shield, a bubble appeared. It seems like I put my case on too soon and the shield didn't have enough time to fully dry, causing this to happen. Again, reiterating what I said before, wait at least 48 hours before putting a case back onto your phone. This assures that the shield has fully dried.
You can pick up a ZAGG invisibleSHIELD for iPhone 4 at ZAGG's official website here: http://www.zagg.com/invisibleshield/apple-iphone-4-cases-screen-protectors-covers-skins-shields.php. The full body protection is going to cost you $24.99, while individual front and back protectors are going to cost $14.99 each.
ZAGG offers a lifetime warranty on these invisibleSHIELD's, meaning you can replace it for free at any point in time if the shield every gets scratches or some other type of damage. If you purchased the protector(s) directly from ZAGG, you are automatically registered to the program. On the other hand, if you purchased them from a third-party retailer, like Best Buy, you're going to have to visit the following website to register your shield under warranty: http://zagg.com/register
Do I recommend it?
While the invisibleSHIELD for the iPhone 4 does have its flaws, I would recommend the shield for anyone looking for easy-to-install protection on their phone. With that in mind, keep in mind that these shields aren't for everyone and many people don't like them.