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Computerized Investing > September 1, 2012
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by Wayne A. Thorp, CFA


One-piece silicone rubber case with a built-in battery.

Since its release, the iPhone 4 has been plagued with battery problems. This has led numerous companies to develop cases with built-in batteries, offering the benefits of protection and additional battery life. Back in May, I reviewed the mophie juice pack plus, which has been my preferred case ever since. I love it for the added juice, but it really proved itself when, recently, a less-than-sober friend of mine decided to toss my iPhone around a bar. The phone came away without a scratch.

As a result, I’ve been a little wary of trying out a new case. However, I’ve been testing out the PowerSkin for iPhone 4/4s to see if it can match the mophie’s battery life and protection.

Out of the Box

The PowerSkin is a one-piece silicone case with a hard plastic back. This makes it unique, since most cases, including the mophie juice pack plus, are composed of two pieces that slide together, encasing the phone. Some reviewers see a one-piece unit as an advantage, since there is no risk of the two pieces coming apart (something I have never experienced with my mophie, even after being tossed and dropped like a hot potato). I don’t like the one-piece design because you have to insert the phone into the dock connector at an angle. I am not sure what kinds of stress this puts on the phone, but I wouldn’t want to be taking the phone in and out of the case too often. By comparison, removing and reattaching the mophie case was a breeze.

Aside from having to force the phone into the dock connector, installation is straightforward. After sliding the phone into the dock connector, the soft silicone sides wrap around the edges of the phone. For those looking for full-screen protection, you don’t get that with the PowerSkin (which is typical for these kinds of cases).

Compared to the mophie, the PowerSkin’s dimensions are almost identical: 5.1 inches by 2.5 inches by 0.77 inches. With roughly equal dimensions and equal 2,000 mAh power capacities, the PowerSkin weighs 15% more than the mophie juice pack plus (2.88 ounces versus 2.5 ounces). This brings the total weight of the iPhone and case to nearly a half of a pound. If you want to protect your phone and increase the battery life, this is the price you pay (in addition to the $80 cost). Even with the added bulk and weight, however, the PowerSkin will fit in a pocket.

The PowerSkin covers the iPhone’s sleep/wake button and volume buttons, but these buttons are molded into the case’s edges, making their operation relatively easy (although I did find I had to press harder with this case than I had to with the mophie case). The edges are not as thick as they are on the mophie juice pack plus, so the mute/ringer switch is easier to access. There are cutouts for the headphone jack and rear-facing camera too. At the bottom right of the case is a micro-USB port for simultaneous syncing and charging. Unlike the mophie juice pack plus, the PowerSkin automatically syncs your phone with iTunes when you plug it into your computer. I was disappointed to discover, however, that the PowerSkin would not work with my PowerMat charging station. When I plugged it in, the PowerSkin kept switching on and off and I couldn’t figure out a way to fix the problem. This is something to keep in mind if you use a third-party charging device.

On the bottom of the case are four lights that indicate the charge level of the battery as well as a combo battery check/power button. To turn the battery on or off, you hold this button for two seconds. I prefer the power toggle switch of the mophie case, which shows you when the battery is on or off.


Like mophie, PowerSkin claims that it will double the battery life of your iPhone, offering over eight hours of additional talk time on a 3G network and 350 hours of standby time. Living in Chicago, I am on AT&T’s pseudo-4G network. This is more taxing on battery life, so my experience isn’t quite as good as PowerSkin claims. I have found that I can get about six hours of talk time with my PowerSkin. Still, this is nothing to scoff at.


The PowerSkin battery case definitely gives the mophie juice pack plus a run for its money. Being as paranoid as I am, I would have given the nod to the PowerSkin in terms of protection, given its added weight versus the mophie. However, having seen the mophie in action, I know for a fact that it can protect my iPhone from some pretty serious abuse. Furthermore, mophie seems to have paid a little closer attention to detail. I like the dedicated power switch and the more responsive buttons that you get with the mophie juice pack plus. Also, I like the fact that the two-piece design doesn’t put stress on the phone’s connector when installing it or removing it.

Whether or not these issues, which are relatively minor, make up for the mophie’s higher cost is a matter of personal taste. The PowerSkin is available from the company’s website for $79.99, making it 20% cheaper than the mophie juice pack plus.

Since the mophie passed my real-life stress test, it gets my nod in this head-to-head battle.


  • Long battery life
  • Sturdy construction
  • Battery indicator life


  • Wouldn’t work with my PowerMat charging station
  • Installation puts stress on phone’s connector
  • Heavier than other battery cases
  • Doubles thickness of iPhone

PowerSkin for iPhone 4/4s

$79.99 (Currently $49.95 from

Wayne A. Thorp, CFA, is the author of "Gadget Corner." All reviews are based on firsthand experience of the product or service. No third-party compensation is received for opinions on products, services, websites or topics. However, sometimes the author is not required by the manufacturer or their PR firm to return the product under review. In such instances, it is our policy to convey this within the review. The views and opinions expressed in these reviews are strictly those of the author. Any product claim, statistic, quote or other representation about a product or service should be verified with the manufacturer or provider.

Wayne A. Thorp, CFA is a vice president and senior financial analyst at AAII and editor of Computerized Investing. Follow him on Twitter at @WayneTAAII.


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