NEW DELHISmartphones have gotten better in recent times concerning battery capacity and charging times (with Oppo and OnePlus leading the way), battery life in general has not improved as much as other areas of technology, because of the demand for thinner smartphones.

As a result, all of us need to use the lifesaver called the power bank. These devices have become the default accessory to pair with any smartphone. Power banks are increasingly important, particularly if you spend any time outdoors, rather than near an outlet.

Looking at Amazon and Flipkart , you can see that the marketplace is flooded with power banks, with different specifications from a wide range of brands. How do you know which one is the right one for you? Heres what you need to consider before buying a power bank:

Portabilitysize and capacity trade-offs

Weight is the most important thing to consider when purchasing a power bank. You dont want to buy something that will weigh down your pocket/bag. Power banks with bigger batteries may offer more ports and a larger number of charges per cycle, but the trade-off is that they are heavier too. Finding the right balance is necessary, and most people will find 10,000mAh batteries as the right kind of compromise. This should fit comfortably in a pant or jacket pocket, and charge your phone twice too. Any larger and youll need to carry a bag with you.

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Ports and charging

The more ports the battery has, the more devices you can charge at the same time. The type of ports also affects which devices can be charged using the battery, and also the speed of charging. The bare minimum is one micro-USB input, and one USB-A output.

But as USB-C has become more common you should look for this port if thats the type of charger your phone uses. The other advantage is that USB-C allows for faster charging, and brings input and output to a single port.

Fast charging and/or wireless charging

The next thing to consider is whether or not you want a fast charging power bank or a wireless power bank (sans cables). The first thing to determine is whether or not your smartphone supports wireless charging and what is the fastest speed it can be charged at.

For wireless charging, its a simple case of whether or not your smartphone supports it. For fast charging, you have to tick three boxes: A smartphone that is compatible with one of the fast charging standards and a battery and cable supporting the same standard. You need all three for your smartphone to be fast charged via the power bank.