Having a way to charge your iPhone on the go is paramount nowadays, especially since heavy use — looking at you Facebook, Snapchat, and Pokémon Go! — can kill your battery before day's end. When that happens, and there's no outlet in site, a battery pack will be your best friend. But which battery pack? Here are our favorites!

Credit card-sized

TravelCard 1500mAh

You can grab a TravelCard that's made specifically for the iPhone, with a built-in Lightning cable. 1500mAh won't give you a full charge, but it should help you make it to the end of the day, which is really all you can expect out of a credit card-sized battery pack.

$29 at TravelCard

High capacity

RAVPower Ace 22000mAh

If you think you'll need to charge up your iPhone more than once before you see an outlet again, then this high-capacity power bank is what you want. It'll charge your iPhone up 5 times at least, and it's relatively compact, so it shouldn't take up much real estate in your bag.

$42 at Amazon

Candy bar-sized

Anker Astro E1 6700mAh

If you're looking for an exceptionally portable charging option, the Anker Astro E1 is perfect. It's roughly the size of a chocolate bar and should charge your iPhone at least once, if not one and a half times. Comes in four colors.

$24 at Amazon

Budget pick

Aibocn 10000mAh

10000mAh should charge your iPhone a couple times, and this power bank comes with a built-in flashlight, making it perfect for camping or in case of an emergency. You can charge two devices simultaneously at normal speeds.

$11 at Amazon

Fast charging

Anker PowerCore+ 26800mAh PD charger

If you want to fast charge your newer iPhones, you'll need a power bank that offers USB-C Power Delivery like this one. It'll charge your iPhone at least six times — all you need is a USB-C to Lightning cable, and you'll be able to charge the iPhone 8 and later as quickly as possible.

$130 at Amazon

Pocket-size

Jackery Bolt 6000mAh

Jackery's Bolt is a slim option with a built-in Lightning cable, so there's no need for you to carry one around with you. With 6000mAh, it should be able to juice up your iPhone at least once. And if gray isn't your thing, it comes in a vibrant orange.

$30 at Amazon

Built-in A/C

Ventev Powercell 6000mAh

Ventev's Powercell charger has a built-in A/C connector, as well as a built-in Lightning cable, so it's everything you need for charging up your iPhone and for charging the power bank itself, all in a portable package. The LED status indicators are the icing on the cake.

$50 at Amazon

Solar power

Be-charming 24000mAh solar charger

This high-capacity power bank has a solar panel, so once its 24000mAh battery is depleted, you can leave it out in the sun to charge, making it perfect to take on camping trips and long hikes. It will take a long time to charge in the sun, but it's still a great feature.

$30 at Amazon

A portable power bank is the best way to make sure your iPhone keeps going until the end of the day or even a couple days if you go with the right one. For $50, the Ventev Powercell is my favorite charger, with its built-in Lightning cable and A/C connection — it's the most convenient option on this list.

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