How we test phones

Every phone we review is put through a series of benchmark and real-world tests. Most phone reviews will be conducted over the period of a week, with updates added to the review following any software upgrades or new features.

We always use the review device as our main phone, transferring everything across along with the SIM card. Here’s what we test for:

Our technical tests and benchmarks

We run every phone we review through a formal benchmarking process, but in our view what matters more is how it performs in real-world use. Nevertheless, benchmarks are useful for comparative context and whether we can expect the phone to be as fast next year as it is today.

By using the review device as our main phone, we can evaluate how a device will handle everyday tasks. How accurate is the GPS when using mapping apps? Does it play all the latest games? Is there noticeable lag when carrying out ‘basic’ tasks such as messaging, web browsing and switching apps?

We’ll also compare devices to models we’ve reviewed previously, and take price into consideration. However, even cheap phones need to be powerful enough to handle basic tasks.

• We test gaming performance through a few intensive titles (Real Racing 3, PUBG Mobile, Asphalt 8) and few lighter ones (Alto’s Adventure, Dots). We’ll always state in reviews which games we’ve used.
• In terms of benchmark apps, we use Geekbench 4, the latest version of AnTuTu (Android only) and 3D Mark’s Sling Shot (for higher-end devices). Geekbench tests CPU performance with a single-core and multi-core score, while AnTuTu is a little broader and tests everything from storage speed to scroll speed. Sling Shot puts both the CPU and GPU to the test, informing whether a phone is also a good 3D gaming device.

Other areas tested are call quality, speaker performance, Wi-Fi performance and signal strength. These are all done through comparisons with other devices in a similar price range and under the same conditions.

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Assessing the display/screen

The screen is one of the most important features of a phone, whether you’re buying a budget or flagship device. After all, it’s the part of the handset you’ll look at and interact with the most.

Visual inspection: screen tests are carried out by eye and involve comparisons with similarly priced models. We test brightness in varying conditions (a dark room, bright room, outside in strong daylight) and the degree of brightness of which the phone is capable – whether it can get really dark and really bright. For example we test whether it can be adjusted to a low enough level for comfortable viewing at night without distracting others.

Colours: another important area we examine is how the display handles colours. Are they realistic? Too saturated and brighter than they should be? A bit dull? Many phones, especially the flagships, have multiple screen modes that alter the colours and vibrancy. We evaluate all these options and advise which works best for a specific scenario.

Black and white levels: these are vital for a great screen, so we’ll always compare several similarly-priced models to see which comes out on top. A screen whose whites appear to have a yellow tinge and no uniformity are considered poorer, while those handsets that have an LCD will be unlikely to achieve the black levels of an OLED.

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Design, build, durability

If a phone we review is sold on the basis of being ‘durable’, we’ll try as much as possible to see if that claim is true. This could include dropping it from a certain height onto a hard floor, or doing our best to imitate a rough environment. Not all phones will be put through such tests unless its durability is claimed, and marketed, by the manufacturer.

Since we use a handset as our main device throughout the review process, we’ll make it clear if we feel it picks up scratches too easily. Unless a case is included in the box, we’ll use the review unit without added protection.

We’ll test water-resistance ratings by submerging into water for the manufacturer-quoted limits and whether a device offers dust protection alongside any other claims made by the manufacturer.

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Real world camera tests

When judging a phone’s camera we take multiple pictures in the following situations and environments.

• Daylight landscape – this gives a good indication of colour reproduction and detail
• A close-up – great for determining detail
• Low-light indoors
• Low-light outdoors
• Selfie – testing out the front camera
• Portrait – how does it deal with skin

We’ll also shoot hundreds of pictures of everyday items, depending on what we’re doing the week we’re testing the device. We then view these images on a calibrated BenQ SW271 monitor.

Included in the review of a phone will be multiple photo samples uploaded at full resolution. However, these will be slightly compressed due to the nature of our website. Each photo sample is accompanied by a caption that gives an explanation of the photo and what is shows.

Video samples will also be shot in varying resolutions, depending on the settings the phones offers.

If a phone offers special features, such as Bokeh effects or slow motion video recording, we will test these too.

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Battery life tests

We conduct several battery tests on every phone we review. These include:

• An hour of Netflix HD (where available) streaming
• An hour of Spotify streaming with the screen off
• 30 minutes of intensive gaming (game will be noted in the review)
• 30 minutes of light gaming (game will be noted in the review)

Each of these is done with regular options such as Wi-Fi and cellular connectivity on and the screen set to a comfortable level of about 45-55% brightness.

We refrain from these tests until we’ve been using the phone for a number of days. The first few days are often spent carrying out multiple app installs and intensive processes, which deplete the battery very quickly. We also let the battery settle down before we properly test it.

However, the most important test is to see how the battery performs under normal use. Reviewers keep a diary of battery drop during normal use, assessing questions like: were we concerned that it wouldn’t see it through to midday? Or did it comfortably last until bedtime?

We’ll also test charging speeds to determine the length of time it takes to charge the phone from 0% to 100% using the supplied charger. If the phone advertises wireless charging, we’ll test that too.

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Scoring and final verdict

After all the tests are complete, we score the phone using the criteria outlined here.

We first check to see if the phone’s performance matches the manufacturer’s claims, and that all the features work as expected and advertised. We look at how it compares to other similar products, if it’s missing any vital features and whether it impresses as a whole.

Value is a consideration during scoring, too. If a competing product offers equivalent features for less money then this will affect the score. Equally, if a device is only slightly more expensive but performs significantly better then we’ll judge the product accordingly.