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Find your next upgrade with this ultimate mobile phone guide

Published 9th December 2022
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On the hunt for a fresh mobile phone? There's never a bad time to buy a smartphone, but sifting through all the models, specs and features can take up a lot of time - unless you read this guide!

From iPhones vs Android phones to the difference between used phones and refurbished phones, we'll help you find the ideal perfect handset in no time!

Close up on women's hands typing on phone

Mobile phone features explained

Look at a phone's specifications page and you'll see a mass of incomprehensible figures, many of them irrelevant to the average user: here's what you need to choose the right phone.

Screen size

There are two ways of measuring screen size: inches and resolution. The first tells you physically how big the handset is - larger phones are wonderful if you want to watch movies or TV via streaming, or for multitasking, but they can also be a pain to fit in your pocket!

Resolution tells you how detailed your phone's display is and is measured by height and width in pixels. The higher the numbers, the sharper text, icons and videos will appear.

Many mid-tier phones will have a resolution like 1600x720, while the latest high-end models will be much larger. The Google Pixel 7 Pro measures a whopping 3210x1440.


From holiday snaps to selfies, we love taking photos with our phones - but how do you know if your phone has a camera worth using?

The best way to tell at a glance is the megapixels (MP) - the higher that number, the sharper your photos will be.

Top-rated camera phones have 40-50MP sensors, like the Huawei P50 Pro. Look out for extra software features like image stabilisation and auto-HDR which can make up for fewer megpixels.

Processors & RAM

These parts are responsible for running all the apps on your phone, including background services like your Wi-Fi and antivirus protection. More premium smartphones will have much larger processors and RAM.

Storage capacity

This is the simplest feature to explain: all your photos, videos, apps, downloaded music and so on take up digital storage space, measured in gigabytes (GB). The more storage space you have, the more you can fit on your phone.

The most common devices are 64GB phones and 128GB phones. You opt for more storage, or alternatively, you can offload a lot of your data to cloud storage systems like iCloud or Google Drive - just make sure you have a mobile connection!


We keep a lot of private information on our phones, so it's important to keep them safe from prying eyes. Every phone offers a basic PIN lock, but some offer more advanced security features.

Many handsets now include fingerprint sensors or facial recognition systems like FaceID. Not only do you not have to remember a password again, but they're also more secure.

Battery & charging

A decent battery is less exciting than other features but extremely important - you'll soon tire of always plugging your phone into the charger!

Batteries are measured in mAh (milliamp hours): the bigger the number, the longer your phone will last on a single charge.

In recent years, charging tech has come a long way. Look out for phones with fast charging - they'll go from totally flat to 100% in an hour or so and just fifteen minutes of charging can give your phone enough juice to last for a couple of hours.

Water resistance

You shouldn't use your new phone while in the bath, but if you're going to, make sure to buy a phone with water resistance!

For maximum protection, choose a model with IP68 protection like the OnePlus 9 Pro. While this can protect your phone from accidents, it doesn't make it totally waterproof, so no texting in the tub!

Woman comically holding up two holds

iOS vs Android

iOS and Android are the most popular smartphone operating systems (OS). An OS controls all of the features and systems of your phone - if your phone doesn't have an OS, it's not smart!

Both iOS and Android have the same core features, but there are some subtle differences between them. It's important to choose wisely, since you can't swap between them once you've bought your phone.


  • iOS is made by Apple, so it's only on iPhones.
  • A more stable, curated experience: Since Apple designs the handset and software themselves, iPhones tend to be less prone to crashes or errors than Android devices.
  • Better range of accessories: Since only Apple makes iOS phones, third-party companies are more willing to sell accessories like phone cases.
  • Advanced privacy controls: iOS lets you opt out of apps tracking you across your phone, helping you keep your privacy intact.
  • Better security features: Lots of phones let you unlock your phone with your face, but so far Apple's FaceID is the most secure. Also, Apple supports its phones with software updates for much longer than other brands.


  • More phones to choose from: Google allows anyone to use Android, making it the standard for almost all phone manufacturers.
  • The best choice for budget: There are lots of budget-friendly Android phones to choose from, whereas you'll have to go used or refurbished to find a low-cost iPhone.
  • Customizability: Android gives you more freedom to customise your phone's software with launcher apps, keyboard apps and more. It's also easier to 'side-load' apps from sources other than the Google Play Store.
  • Expandable storage & headphone jacks: Many Android phones have a MicroSD card slot so you can add more storage, something Apple doesn't allow. Another feature absent from iPhones is the headphone jack, which most Android phones still have.
Trio of different phones held by different people

Smartphone brands

The world's biggest technology brands are fighting it out for the top smartphone spot, so there are plenty to choose from. Here's a list of the top ones:

Person repairing phone

Used & refurbished phones

If you want a premium phone but can't afford the RRP, buying a used or refurbished one could be for you. These help give second-hand phones a new lease of life and save them from the landfill, so it's good for the environment as well as your wallet!

Used phones have been someone else's device for a while, although that can mean 12 months of use or less (some tech fans are always upgrading their handsets). That means they won't be as well-conditioned as a refurbished handset, but they'll cost less as well.

Refurbished phones are a little different. They're usually phones that have barely seen any use. Sometimes that's because of an easily fixed fault that's been repaired, or they've been returned because the original owner changed their mind.

Either way, they work like a nearly brand-new device but cost a fraction of the RRP.

We make it easy to buy used and refurbished phones. When you're browsing on a model's product page, scroll down to the 'compare sellers' box and you'll see detailed condition notes from each of our sellers.

Close-up of phone in case

Essential phone accessories

To make the most of your new device and protect it from harm you'll want to invest in a few accessories. We'd recommend these:

Now you're ready to work browse our mobile phones category in full!

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