Electronics are a given in any backpacker’s kit these days. Cameras, phones, headlamps, water purifiers, and GPS units are all common items found in any pack. Chances are, some (or most) of these are powered by USB. Traditionally, backpackers have simply carried extra batteries or resupplied in town. With USB devices, that’s not an option. So, how do you charge these USB devices in the field?

While there are many solutions for each situation, I’ll share the solution I’ve found that works best for me. 

On almost every trip I’ve got three electronics; iPhone, steripen, and headlamp. The steripen and headlamp are both powered by disposable batteries. The iPhone, however, is charged via USB.

For many the answer may be to simply keep their smartphone turned off, and only turn it on if it’s needed. This is not an option for me. My iPhone serves many uses. By order of use, it is a camera (both still and video), map, guidebook, reference, notepad, blogging device (blog, twitter, instagram, etc.), entertainment, and finally, a phone¹.

With that in mind, it’s easy to see that it will need to be charged a few times between each resupply on a long trip. To do this, I rely on a mobile battery pack. More specifically, the best one I’ve found is the Just Mobile Gum Pro.

In my experience, if the Gum Pro has a full charge it is able to power my iPhone a solid three full charges. Even under heavy use, this enables me to go a good four days between towns. At that sort of capacity, you’d expect the Gum Pro to be heavy. It’s not. On my scale it comes in at 4.3oz. To make this thing even better, it’s incredibly affordable, costing $49.99. 

You should also be aware, there is a new power pack from Just Mobile available that has the same specs but is wrapped in an Apple-inspired design. This is the Just Mobile Gum Plus Power Pack and it comes in about $10 more at $58.