If your smartphone is constantly running out of battery, a portable power bank (also referred to as a "portable charger" or a "portable battery") is pretty much your only solution short of getting a new one. There are a zillion different options out there, but if you want to charge your smartphone we suggest buying one that is small enough to fit in your pocket.
There are few other things to take into consideration before buying a portable power bank — here's what you should know.
Buy one that uses the same charging port as your smartphone (or laptop).
We recommend buying a portable power bank that uses the same method of charging you already use. If you have an Android smartphone (or laptop that uses USB-C), get a portable power bank that charges via USB-C. If you have an iPhone, get one that charges via Lightning. You can buy a portable power bank that can charge wirelessly, too. This will just make your life way easier using the same cables to charge your smartphone and power bank. I promise.
Buy one that can fast charge.
Most of today's portable power banks are integrated with some type of fast charging technology. The two most popular are Power Delivery (PD) and Qualcomm's Quick Charge. The two technologies are a little bit different. Power Delivery only works with a USB-C to USB-C connection and allows the power bank to better control more watts and deliver more power — basically, they’re able to fast charge larger devices (if those devices support it). Qualcomm's Quick Charge allows your smartphone to charge faster than you would with a traditional power bank (it outputs at 5A rather than 3A).
Buy from a reputable brand.
Finally, you should buy a power bank that's made by a brand you trust. If you go on Amazon or another online marketplace, you'll see a lot of cheap options made by companies that you've never heard of. Stay away. Buy one from a notable brand — such as Anker, Mophie, Aukey or RavPower — and it'll last longer and be more reliable.
Have a new iPhone? Get one that works with MagSafe.
The iPhone 12 and iPhone 13 have a special magnet integrated into them, which Apple calls "MagSafe," that allows that work with an ecosystem of accessories but, maybe more importantly, allows them to charge faster when paired with a compatible MagSafe charger; they can at up to 15-watts rather than 7.5 watts. So if you want to charge your iPhone as fast possible and not deal with a charging cable, you definitely want a portable battery that is fully capable with MagSafe. (For more info, read our guide to the best MagSafe battery packs.)
There are a number of different MagSafe-compatible portable batteries out there, all of which magnetically attach to your iPhone 12 or iPhone 13 so that you can wirelessly charge it on the go — no need to bring a cable.