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A Geek's Primer To Rugged Smartphone And Tablet Cases

You don't want a wimpy case for your new iPad Mini or Google Nexus 10. You want one with the most modern materials so it can survive a fall from a skyscraper and an assassin's bullet.

If you're the type of person that picked your last iPhone case because it matched your pants/eye color/belt buckle, then you can stop reading right now.

Unless, that is, you have seen the ERROR OF YOUR WAYS, having dropped your last smartphone on the street and watched in horror as the glass shattered like pond ice in spring.


Kind of like this.

While you can get cases made from wood, bamboo, metal and other more exotic materials, the vast majority are made out of plastic. The better cases always feature two layers of plastic: a hard outer one, often made out of polycarbonate, and a soft inner one (though the well-known OtterBox Defender comes with THREE layers, while the Ballistic Hard Core comes with UP TO FIVE).

I recently spoke with two experts who explained how much the plastic materials in smartphone and tablet cases have improved in the six years since the iPhone's introduction. 

One is a business manager with one of the leading suppliers of plastics to case makers such as OtterBox, Speck,  Incase and others. Because he is not authorized to speak to the media, I'm not giving his name.

The other is Jeremy Russell, director of sales for G-Form, a Providence, Rhode Island-based maker which claims its cases are more protective than others. How protective? (Click on the images below to watch the videos)


Or enable an iPhone to survive a slapshot aimed at an NHL goalie:


Plastic cases have actually come a long way. Most early cases - or their inner layers - were made with PVC (Polyvinyl Chloride) that was treated to become a soft rubbery material (think pleather).

While soft PVC is reasonably protective, it is very insulating, making devices overheat and sapping their battery life. PVC also tends turn yellow when it gets too hot, says the manager.

As a result, a lot of manufacturers moved to cases that used silicone for shock absorption. Silicone's merits include its soft feel, its resistance to UV sunlight as well as potentially-disintegrating hand lotions. The problem with silicone, at least for vendors, is that it is "very expensive" and "tedious" to manufacture, he says.

Recently, many case manufacturers have switched from silicone to a rubber-plastic hybrid called TPE, or Thermoplastic elastomer, as the inner lining. TPEs are easier to manufacture, resistant to hand oils and lotions and can be made transparent, he says. And unlike bulky foam-type materials, it can be cut to fit the mobile device precisely.

That has been the knock against the cases made by G-Form - that their cases, while protective enough to survive 100,000 foot falls from space, aren't the sleekest on the block.  

It's less about G-Form's design, and more that their cases are based around a special foam called PORON XRD. According to G-Form, the material stiffens upon impact in order to absorb shock.

That feature isn't unique, says the unnamed manager, who says all polymers are, at some level, "non-Newtonian" - meaning they stiffen upon impact.

But G-Form claims it further enhances PORON XRD by blending it with other materials in a special formulation it calls Reactive Protection Technology.

"The magic is in our molding process," G-Form's Russell said, asserting, "We absorb 10 times more energy than other foams of the same thickness."

That makes G-Form cases much more rugged than other cases, including OtterBox, claims Russell. Schools using G-Form cases have been able to reduce their iPad breakage rates from 20% a year to just 1-2 a year, he said.

G-Form is about to introduce a new line of $39.99 Xtreme cases for the iPhone 5 that it says offers the same level of protection but in a slimmer, more stylish package. On looks, you be the judge: