You're stranded, there's not an outlet in sight, and your phone is about to die. Maybe you're at an important event, on a bus, somewhere where you need power but don't have it. Whatever the case, Mophie has your back. When your device is verging on 0 percent, its new Juice Pack Powerstation Duo can get you out of a jam without flinching, power outages be damned.

If you have $100, and the need to charge your device on the go, Mophie's excellent Juice Pack belongs in your gadget arsenal. It will be money well spent. Rather than embarrass yourself by asking a complete stranger to borrow their phone when yours is dead, Mophie will shield you from public shame. Thanks, Mophie.

What is the What?

The Juice Pack Powerstation Duo is a 6,000 mAh external battery for tablets and smartphones. It's roughly the size of a deck of cards (slightly thicker), with dual USB charging ports and one micro USB port. The exterior is a wonderfully comfortable soft-touch, with an LED indicator in the bottom corner so you know how close you are to going dark. In addition, it has a 2.1 amp charging output, so you'll be back on the grid in no time.

Who Might Buy It?

Outdoorsman, farmers, travelers, smartphone / tablet owners, your parents, you. Everyone. If you have a smartphone and have ever experienced battery anxiety, you need to pick one up. It's a purchase for the now, for the future. It is the difference between flatlining and staying connected in an emergency situation. Is your battery about to die? That's an emergency situation in my book.

What's Good?

This should be secondary when purchasing an external battery, but the Duo's design is quite lovely. The soft-touch black material looks and feels quite premium—tablet quality—accented by a metal band. As we mentioned earlier, on the bottom you'll find the dual USB (for charging two devices at once) and single micro USB charging ports, along with a small power button that activates the LED power indicator. Four LEDs means full steam ahead.

The device itself has a 500 cycle life (partial cycles don't count as full, Mophie said), so this will likely last you forever and ever. When I charged my iPhone 5 up from death, the Duo brought it to 100 percent in two hours. That was a test scenario, controlled, so your mileage will definitely vary. 

In all likelihood, you'll probably find yourself charging your device up from 3 or 4 percent up to around 50, so you won't need to sit around waiting for it to become completely full. If I had this at CES, I could have avoided some dire situations—good thing I had a backup device.

Because the Duo is only cranking out power at 2.1 amps, we're not talking about blazing charge speeds here. If you want to charge up an iPad, be prepared to wait around for optimum power. Still, the Duo is equipped with enough guts to power both an iPhone and iPad simultaneously. That's pretty darn impressive. And don't worry about quirky compatibility issues; I was able to charge a Nexus 4 without incident.

What's Bad?

Price, maybe. I did an Amazon search for portable batteries and found several no name options for much cheaper, and with more power. But I have no way of knowing if those are quality products without testing them myself—or reading submitted reviews, I suppose. The Mophie is $100 for 6,000 mAh, while an 11,000 mAh battery from IOGEAR is just $50. You be the judge.

You also can't charge your Duo and a device at the same time. As Mophie puts it, "This device does not have pass-through capability. Please charge the powerstation separately from other devices."

Does it Belong in the Herd?

This is a quality product, built with precision and care. It feels premium, solid, and offers piece of mind for those who experience battery anxiety. The size is fantastic, the LED indicator is convenient, and it has enough power to get your devices out of a pinch. You can also share with other power hungry friends thanks to the Duo'a dual charging ports. If you're nice. [Mophie]

4.5 out of 5

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