Critical Kit: Anker Astro Mini ultra-compact power bank

In this edition of our Critical Kit series, we take a quick look at an essential mobile accessory that anyone who owns a smartphone should find immensely useful – an external battery pack to charge your phone and get you through the day when you’re precariously low on juice.

Can you last all day without a recharge?

There’s nothing worse than your phone’s battery running out at an inopportune moment, especially when there’s nary a charging outlet in sight and you’ve forgotten to bring a charger. And unfortunately, smartphones suck power at an alarming rate, thanks to our constant use of 4G and Wi-Fi and propensity to watch movies, download games and surf the Internet at every available moment.

An external mobile phone charger (or power bank as they are commonly known) is therefore an unfortunate necessity, but they are not all created equally – so what should you look for when choosing a power bank?

Essential power bank features

Several factors besides price are important – portability might be a key factor for example, as some power banks are small enough to slip into a pocket while others are too bulky or heavy to lug around all day. Pay attention to the advertised weight and try and avoid bulky ones if you’re on the go.

Perhaps the most critical factor however is capacity – it’s important to realise that most power banks won’t even deliver their full capacity to your devices, as some of the energy is lost through heat and voltage conversion. Around 70% efficiency is not uncommon, which means that a 10,000 mAh charger usually only delivers about 7,000 mAh of power.

The input rating is also key, as the higher the figure the quicker it can be recharged. Some power banks support a feature called passthrough charging (but you can expect to pay more for that), which simply means they can be recharged whilst simultaneously charging your mobile devices.

And it’s the output rating that determines how quickly you can charge connected devices. In many cases, 1A and 2A outputs are provided – the 1A outputs are for smartphones and the 2A ones are for tablets. You can use either of course to charge USB devices, as they draw only the power required, but some tablets (such as iPads, which are notoriously fickle) won’t charge from lower-specced outputs.

Additional features

Some of the latest power banks have auto-on and off functions, which enables them to charge your phone as soon as you plug it in and turn off when it’s done. There is usually a series of small LEDs on the charger to indicate remaining capacity, but a few models have an LCD display that shows more precisely the capacity left.

A (debatably useful) popular power bank feature is a built-in LED flashlight – great if you’re on a camping trip or at a festival, but if it’s a bulky, high capacity charger you are unlikely to want to use it as a torch.

The very best power banks strive to achieve a balance of capacity and portability, with fast charging, multiple outputs, and features like passthrough charging and even an LCD display.

Anker Astro Mini

The Astro Mini power bank by Anker is the number one selling charger on Amazon UK, and it’s easy to see why. It’s extremely portable (and good looking) as well as being very efficient. Not only is it a bargain £10 (reduced from £40 at the time of writing) but it’s also available in black, pink, blue, silver and gold coloured anodised aluminium that both looks and feels superb.

In terms of dimensions and weight, it’s just 92mm long and weighs 80g, meaning it fits easily into a pocket. As it has a rugged aluminium finish, it’s not likely to suffer any damage but there’s an 18 month warranty provided with the Astro Mini.

Why is the Astro Mini one of the best power banks? In our opinion, even though it’s not the most feature-rich charger, it deserves the Critical Kit accolade as it’s incredibly portable, stylish, and manages to achieve an incredible 90% efficiency thanks to Samsung Grade A cells.

Unlike rival products that only delivery a percentage of their actual capacity, the Mini does well with its relatively small 3,200 mAh – going that much further and certainly enough to charge any smartphone once or twice.

The Anker Mini also features the company’s PowerIQ technology, which intelligently identifies the type of connected device and adapts its charging rate to match. That’s a boon if you have any fussy devices that refuse to charge with other power banks. Furthermore, that’s a little more peace of mind if you’re about to connect an expensive phone to a charger (avoid cheap unbranded Chinese power banks at all costs, by the way if you want to avoid risking damage to your phone).

Despite not having passthrough charging, we the Anker Mini justifiably qualifies as a critical piece of kit for anyone that carries a smartphone around and needs to recharge several times while on the go.

The Anker Mini can be found on Amazon’s UK site here.

Disclaimer: this article is not a sponsored post – Mobile Industry Review has independently reviewed the Anker Mini power bank.