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How we test mobile phones

By Jessica Moreton

Discover how we test mobile phones to find the models with the best screens, cameras and a battery life that will last you all day.

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What makes a Best Buy mobile phone?

We recommend phones with screens that make films and images look great and text easy to read, take pictures that will rival those of a compact camera and can handle the most demanding apps without slowing down.

The video above shows how choosing a Best Buy mobile phone can make life easier. 

We put every mobile phone through a mixture of hands-on assessments from independent experts and technical lab tests to ensure that each of our full mobile phone reviews answers all the key questions you might have, including:

  • Is the screen detailed?
  • Do calls sound loud and clear?
  • Does the camera take great snaps?
  • How long does the battery last?
  • Should I buy it?

Just want to find the best phone for you? Head straight to our mobile phone reviews. Or keep reading to find out more about our tests.

What’s the screen like?

To test how clear and bright the screen is, we watch the film ‘Fantastic Four – Rise of the Silver Surfer’ and look for the detail, smoothness of motion shots as well as assessing the accuracy of the colours. 

We also test each phone in various light conditions, so we can tell you whether the screen is easy to read even in bright, sunny weather or if the contrast fades away leaving you with a screen you can’t read.

Do calls sound loud and clear?

To see whether it’s up to the job of having a natter to your friends and family we test the call quality vs a BT home phone. But we don’t stop there; we also make a call with a noisy café sound track playing in the background to see how it copes in a more challenging environment. 

The track is played at 74dBA – that’s somewhere between the level of the average alarm clock and normal street noise. We listen to see whether you and the person on the other end of the line can be understood. 

How well do the built-in cameras work?

We capture a variety of photos at long and close range so we can tell you if the main camera can take a decent landscape shot as well as an up close and personal profile. Our test photos feature a weird and wonderful range of objects, from a fluffy teddy bear to a wicker chair. These are used so our experts can assess whether the camera picks up texture. 

We also examine how it copes in low light conditions – which we affectionately refer to as the ‘pub shot’. And it’s only fair that we take a couple of photos with the front-facing camera, too, so that we can tell you whether it’s any good at snapping selfies.

How good is the music player?

With many of us using our phones instead of carrying around a separate music player, we run a listening test to see what it’s like when playing your favourite tracks. We use a pair of standard headphones (Apple earbuds) to play six different tracks which represent a range of genres, running from bass-heavy pop numbers such as Janet Jackson’s ‘Rhythm Nation’ to Rachmaninov’s Symphony no.2 - a true test of their ability to handle detail.

How long does the battery last? 

Nobody wants a phone that runs out of charge before the day is done, so we charge the battery up to full before timing how long it lasts when making continuous calls. We then charge it up all over again and time how long it lasts when browsing the web via 3G. These tough tests tell us whether it will go the distance or if you’ll be reaching for the charger before lunch.

Should I buy it?

71%The score mobile phones need to earn our Best Buy recommendation.

Each of the assessments described above contributes to a total test score, so that you can see which phones are the best and worst, and how each one compares to other models. We focus on overall usability, including screen, battery life, processor power and call quality, and don’t take price into account. The total score breaks down as follows:

  • 50% overall phone use
  • 15% camera
  • 15% media playback
  • 15% web browsing
  • 5% build quality

A mobile phone needs 71% in our tests to earn our Best Buy recommendation. Mobile phones that score 40% or less are labelled Don’t Buy models to make them easier to avoid.

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