It's a decision that many people spend months mulling over – which smartphone should you go for? 

With options ranging from fancy foldables to retro dumbphones, choosing a device can be stressful. 

Thankfully, help is at hand, as the experts at Which? have uncovered the best and worst brands for faults. 

The team analysed 15,644 smartphones from 14 popular brands, including Apple, Samsung, Nokia, and Huawei.  

And their results might raise alarm bells if you were thinking of splashing out on a new iPhone or a Samsung handset. 

'Smartphone brands differ a fair bit when it comes to chances of developing a fault over the first few years,' Which? explained. 

'And it might surprise you to see where the most popular brands, Samsung and Apple, are placed.'

So, how does your smartphone stack up against its rivals? 

For the study, Which? analysed 15,644 smartphones purchased in the last seven years to understand how and when faults happen. 

The results revealed that fault rates for most brands were quite low in the first year of ownership. 

However, it was a different story for many devices in the long-run. 

Sony and Huawei phones were found to develop the most faults after six years of ownership, while OnePlus, Realme and Google developed the least, with just 11 per cent seeing faults within six years. 

'With Oppo releasing five handsets in the last year, they might be a brand worth considering,' Which? said. 

'Realme doesn't release as many, but they're clearly pretty reliable.'

Samsung and Apple were 'middle of the road' for the number of faults they develop, with 13 per cent and 15 per cent in six years, respectively.  

'On average only 8% of smartphones develop faults within three years according to our survey, so most should be in decent shape for a while after a purchase,' Which? reassured. 

In terms of the faults themselves, battery problems were top of the list, respresenting 29 per cent of all faults reported. 

'This includes instances of phones losing charge quickly, but the most common are reports of the battery life getting significantly worse over a short period of time,' Which? said. 

Experiencing a slow or sluggish phone was the second most common fault (five per cent). 

This was followed by phone freezes (five per cent), device crashing (four per cent), and software update problems (three per cent). 

In contrast, fingerprint and facial recognition problems were the least common faults. 

'Our survey data suggests there's no reason to be with less than 1% reporting these problems,' Which? reassured. 

'Instances of phones catching fire or producing smoke also came in at 1%, as did the phone stopping turning on at 1%, and speaker failure at 1%.'

With fault rates fairly low, the researchers instead suggest focusing on security updates. 

'The longer a phone is without security patches, the higher the risk becomes,' Which? advised. 

'The best manufacturers support phones for at least five years from the phone's initial release date. 

'This includes Apple, and some Samsung and Google phones. 

'The worst only support some handsets for two years.'