It might be hard to remember, but before smartphones, we had no need to worry about our phones dying. The phones themselves were marvelously efficient, sometimes lasting weeks on a single charge, and they were also garbage that couldn’t do anything fun, so we didn’t really use them that much anyway.
Most smartphones now last about a day before dying. An intensive session — streaming video, playing games, using turn-by-turn GPS navigation —could kill them even faster than that. And therefore many companies have thoughtfully begun to sell external battery packs, which are usually quite cheap and can be tossed into a bag or purse for those times when you really need to listen to a podcast on the subway home but are down deep in the red, just a few lines of pixels remaining within your transparent battery symbol.
External battery packs vary in capacity, which affects how many times you can refill your phone’s battery; they vary in amps, which affects how quickly your phone recharges; they sometimes have built-in cables for iPhones or micro-USB cables for basically all non-Apple devices, or just a USB port so you can supply your own cable; and sometimes they vary in shape, from batteries that snap onto a phone like a case to credit-card-sized thin batteries to big ugly clunkers.
The question is: Which one should you buy? The external battery pack is a very rewarding category to shop for because basically all of them are fine, but it’s easy to end up with a slightly better one, and feel really great about your shopping prowess.
So: Here are three tips to make shopping for your smartphone battery-pack easy.
Get a battery with an amp count over two.
The most important number to remember is the amp count, which measures how fast the battery is charging. You’ll want an amp count of more than two, which could be labeled with the specific amp rating (2.4, say), or labeled as “fast charging” or something like that.
Understand the battery’s capacity.
Capacity is directly related to the physical size of the phone’s battery pack. The iPhone 6s Plus, a very large phone, has a battery capacity of 2,750 mAh. The Samsung Galaxy S7 Edge has an even bigger one, at 3,600 mAh. The regular iPhone 6s, for its part, has a battery capacity of 1,715 mAh. The tiniest battery packs, like this Anker, have a battery size just around the same size as a large phone’s (the Anker’s is 3,350 mAh). A giant battery, like this one from RavPower, can handle 16,750 mAh.
So ask yourself how many times you want to be able to charge your phone fully. Once, just for an emergency? Get a pocket-sized pack. Twice? Shoot for a battery at around 7,000 mAh. Eight times while you’re on vacation in the jungle? Get the tank.
Forget all the numbers and just get one of these.
Here’s the big problem with most battery packs. Say you’re going on vacation, and need to bring your convenient, portable external battery pack. If you have a standard battery pack, here’s what you’ll be bringing:
1) Your phone
2) Your external battery pack
3) Your cable that goes from the phone to the battery pack
4) A wall charger
5) Another cable to charge your external battery pack (most battery packs use micro-USB, iPhones do not, so you’ll need two different cables to charge those two devices)
6) Maybe even another wall charger, if you want to charge your phone and battery pack at the same time
This is too much stuff! My solution is to get one of the damnably, inexplicably few external battery packs out there that have prongs for a wall-charger built right in. Monoprice makes a few (this $15 model, with a one-charge capacity of 3,000 mAh, is nicely small, but slow, at only 1 Amp of charging power), as does Zagg (for $16, twice the capacity of the Monoprice with a fast 2.1-Amp speed). Here’s what you bring for these things:
1) Your phone
2) Your external battery pack
3) The cable that goes from the phone to the battery pack
That’s it! You can use the battery pack the way you’d use any other pack, but you can also plug it right into the wall to charge it. Even better, when it’s plugged into the wall, you can plug in your phone, and your phone and the charger will both charge simultaneously. It’s clean, it’s neat, no need for extra garbage.