3 Smart Choices for Charging Your Smartphone On the Go

Life Lesson: If you’re going to be off the grid, always carry a backup battery bank for your phone. It’s a simple thing, but it could save your life.

I go road cycling two to three times each week. I always carry my smartphone (a newer Google Pixel model). When you’ve biked as many miles as I have, you’re bound to have few run-ins and accidents.

One time, I dashed out in the dimly lit morning hours to get to my bike ride for the day. I left my house without a spare inner tube. And, of course, I flattened my tire that day. Thankfully, an Uber ride was just a smartphone app away.

Another time, my riding partner was in a bad accident. I was glad I had my phone to call for help.

So it should come as no surprise that my biggest fear is not what could happen on a bike ride, but what would happen if I couldn’t just call for help from wherever I am.

You would think I would always have my cell phone charged and ready to go. But stuff happens. I get distracted. And I end up forgetting to charge my phone.

Heaven forbid that happens on the same day I have an accident. Nothing is more frustrating than remembering to bring your phone, but then realizing you’ve only got five percent battery left and nowhere to charge up.

And as a trader, although it isn’t life-threatening, sometimes I’m out somewhere—like running errands—and I want to enter or exit a trade. I need to be able to count on my smartphone being available with plenty of power while I’m using my trading app.

So I decided to get myself a portable battery bank for my smartphone. Here’s what I learned in the process.

Battery Bank Basics

Battery banks (aka portable smartphone chargers) solve your recharging problems when you forget to charge your phone, or when you’re planning to be ‘off-grid’ for a few days. Whether you are hiking, biking, or traveling abroad, having a fully-charged smartphone is a life saver.

Portable smartphone chargers are one trick ponies. They charge your phone. That’s it! Of course, they can be used for traditional cell phones (like old-style flip phones), too. You can find these portable power banks everywhere: your grocery store, Staples, Wal-Mart, and even the corner gas station.

The Top Performer

As you might have guessed, not all battery banks are made the same. I’ve bought several brands of portable battery banks from Amazon. I have tested them out in extreme situations. There are definitely good brands and poor brands.

In my experience, there is one brand that stands out as the top performer: Anker. I’ve taken Anker products on a 100-mile Century Bike Ride and a 26-mile backcountry hiking trip. So I can tell you they work when it counts.

How Much Power Do You Need?

To choose the power bank that will work best with your particular situation, consider these questions:

  1. How much power does your smartphone use?
  2. How many off-grid recharges will you need for your phone?

Power banks are rated in milliamp-hours (mAh). Milliamp-hours measure energy over time. The higher the mAh, the more capacity the battery has.

As a general rule, the bigger the screen, the more power your device will use. Although each model of phone is different, a nice ballpark number for the power used by a smaller-screen smart phone (like an iphone) is 2000mAh. Larger screens (like a Galaxy Note) will typically take more like 3000mAh. (A tablet will use about 4000mAh.)

Power banks are typically available in sizes ranging from 2000mAh up to almost 30,000mAh. Bigger numbers mean you can charge your phone more than once, or you can charge a tablet.

While ballpark numbers are nice to know, It’s better to know exactly how much power your specific phone will need. You want to be sure that the charger you buy has at least as much capacity as your phone’s battery.

To find this out, look at your phone’s list of specs, under ‘Battery.’ For example, you can see from the table below that, although the capacities are fairly close, each of 3 models of iPhone has a different battery capacity.

The Tradeoffs

Of course, the power banks with the most charging capacity are also the largest and heaviest. So choose a power bank with an eye to your intended purpose. If you’re planning an extended camping trip, you might be willing to lug along more weight than if you’re just backpacking for a few hours.

Here are three categories of power banks. I own at least one from each category, so I can match the power bank to the demands of my activities.

Pocket-Sized Portable Chargers (2,000mAh – 10,000mAh)

As the name suggests, pocket-sized portable chargers are very small and lightweight. They easily slip into a pocket, purse, or briefcase.


  • You have a smaller-screened smartphone.
  • You only need to charge one device.
  • You need a just-in-case back-up so you’ll always be able to make one last phone call or text.

I stay away from the smallest, super-inexpensive models. They generally don’t live up to my quality expectations.

Compact Chargers (10,000mAh – 20,000mAh)

Compact chargers are a nice middle ground with higher capacity than a pocket-size yet still small enough and lightweight enough to satisfy weight-sensitive packers.


  • You have a smartphone that requires more power (i.e., more mAh).
  • You want to be able to charge your phone 3 or 4 times.
  • You want to be able to charge a couple of devices one time.

High-Capacity Chargers (20,000mAh  – 26,800mAh)

High-capacity chargers give you the most power, but also the most weight (at over one pound).


  • You plan to need 7 or 8 charges on a smaller-screen phone.
  • You need to charge several devices one time.
  • You need to charge a large-screen smartphone or a tablet a couple of times.

One More Thing

In addition to capacity and weight, another factor in choosing a charger is the charging amperage. If you want to be able to charge quickly, or if you need to use your device while it’s charging, be sure your charger has at least one 2A (2 amp) port.

To learn more about power banks, check out these excellent articles from Belkin (for the basics) and How-to Geek (for a more technical explanation).


Our phones are our lifelines. But they aren’t any good without battery power. Plan ahead and make sure you won’t run out.

There are more trading computer tips like this in our buyers guide. Check out our “How To Buy a Trading Computer” e-book.

We hope today’s Quick Tip helped you. If you found this helpful, you’ll want to check out the other computer How-To’s I’ve created on this page. You can always call us if you have questions: 800-387-5250