Just Mobile Gum Max Backup Battery Review

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In the first post of this two-part series, we looked at the Just Mobile Gum Plus backup battery. (Read the review, here.) It provides 5200 mAh of battery life and lets you charge your iPhone a number of times. The Gum Plus is small and light enough for you to easily throw the battery into your gadget bag and carry it all the time.

But what if you REALLY need extra battery life? What if you have an iPhone and an iPad you need to keep charged? What if you can’t be sure you’ll be near an outlet at all during the day, and you will be using your mobile devices nonstop? In other words, what if you are attending CES 2013, and you know from past experience that CES is a “mobile device battery suck”?

That’s where the Just Mobile Max backup battery comes in. It’s big, it’s heavy, and it’s pricey — but boy, does it packs a punch!

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From Just Mobile:

Supercharge your iPad! Just Mobile Gum Max is the supercharged backup battery for iPad. With a colossal 10,400 mAh capacity, and 2.1A current, the aluminum-clad Gum Max™ is by far the most ambitious backup solution to the already amazing iPads. It can also fully recharge an iPhone 4S six times, and still have juice to spare. With its standard USB output port, Gum Max™ charges other smartphones and USB devices.

Its USB output allows you to charge most smartphones, too. Eight LED power indicators help you keep track of Gum Max™’s remaining power, and it’s easy to recharge from a standard USB output – so no matter how much you use your gadgets, you’ll never have to be caught short of juice.

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  • Compatible with all iPads
  • 2.1A output
  • 10,400mAh Li-Ion battery
  • Apple certified – works with iPad, iPod and iPhone
  • Apple dock connector and USB-to-microUSB cables included
  • Travel pouch included
  • High-grade aluminum shell

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What’s in the Package?

  • GumMax
  • Dock connector to USB cable
  • USB charging cable
  • Carrying pouch
  • User manual

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The Gum Max has the same design as its smaller sibling the Gum Plus, but it has twice the capacity. That means you can charge it up and it will keep you going and going and going. Judie carries the MiLi Power KingJust Mobile Gum Max Backup Battery Review, a long, thin, and relatively heavy backup battery that has 18,000mAh; she swears by it during the long days at trade shows and gear junkets. I think I prefer the boxier shape of the Gum Max , however, as it doesn’t take up as much space bag; it also doesn’t cost as much as the Mili. Still, at the end of the day all that really matters is that a battery offers a decent amount of extra charge and delivers it safely to the device being charged.

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Simplicity is the key here. On that front the Gum Max delivers with ease.

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There is a microUSB port for charging the battery and a full-sized USB port for transferring the over to a hungry mobile device. One button turns the battery on and off, and a series of hidden LED lights gives you the current charge status. That’s all there is to this battery. It is simple, stylish, and it gets the job done.

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There’s no question that the Gum Max is a big battery. It is about three times as thick as my iPhone 5 and almost as long; it is also wider.  It comes in at 4.3″ x 3.3″ x 1.0″ and 9.62 oz. Compare that to the iPhone 5 which comes in at 4.87 ” x 2.31″ x .30″ and  weighs 3.95 ounces. Yeah, it’s a big battery, but that is the idea.

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Here’s the Gum Plus sitting atop the Gum Max. Neither is small, but the Gum Max certainly overshadows its smaller sibling.

And speaking of the smaller battery, as with the Gum Plus, Just Mobile also includes protective bag and a few cable adapters with the Gum Max. The cables work fine if you have a last generation iOS device, but you won’t be able to charge your current generation Apple iOS device unless you supply your own cable.

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Here’s the Gum Plus atop the Gum Max, atop the iPhone. It’s a lot to carry around, but when you combine the two batteries you get almost 16,000 mAh of extra power. That will certainly go a long way during the insanity that is CES!

The Gum Max is simple, big and it gets the job done while looking pretty cool. It certainly has a place in my 2013 CES Gear Bag! You can learn more about the Just Mobile Gum Max here on the company site.

MSRP: $129.95

What I Like: Big and powerful; Simple but effective; Strong and comes with a carry pouch

What Needs Improvement: Heavy; Pricey; BYOLC (Bring Your Own Lightning Cable)

Source: Manufacturer supplied review sample

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About the Author

Dan Cohen
Having a father who was heavily involved in early laser and fiber-optical research, Dan grew up surrounded by technology and gadgets. Dan’s father brought home one of the very first video games when he was young and Dan remembers seeing a “pre-release” touchtone phone. (When he asked his father what the “#” and “*” buttons were his dad said, “Some day, far in the future, we’ll have some use for them.”) Technology seemed to be in Dan’s blood but at some point he took a different path and ended up in the clergy. His passion for technology and gadgets never left him. Dan is married to Raina Goldberg who is also an avid user of Apple products. They live in New Jersey with their golden doodle Nava.