Which mobile phone brands develop the most faults?
Battery problems, crashes, and poor performance are all issues that smartphone owners notice with their devices over time.
And new Which? data based on over 15,000 smartphones purchased in the last seven years, reveals exactly which phone brands develop the most faults and how quickly these can happen.
Fortunately, many can be fixed – either for free or for a small cost. Read on to find out more, and join Which? now to view the full survey results and reveal which mobile phone brand to buy in 2025.
Our guide to the best smartphones for 2025 reveals the models that impressed in our tests.
The best and worst mobile phone brands for faults
As you can see from the table below, smartphone brands differ a fair bit when it comes to chances of developing a fault over the first few years – and it might surprise you to see where the most popular brands, Samsung and Apple, are placed.
| Mobile phone brand | Developed a fault after one year of ownership | Developed a fault after three years of ownership | Developed a fault after six years of ownership |
| OnePlus (142) | 0% | 3% | 11% |
| Realme (47) | 2% | 4% | 11% |
| Google (801) | 4% | 7% | 11% |
| Samsung (5787) | 2% | 7% | 13% |
| Apple (6606) | 3% | 8% | 15% |
| Honor (157) | 3% | 8% | 15% |
| Xiaomi (310) | 4% | 11% | 18% |
Results based on a survey of 15,644 smartphones owned by Which? members and members of the public. Sample sizes in brackets after the brand. Research conducted in March 2025.
It's somewhat reassuring to see that fault rates for most phone brands are quite low after the first year of ownership, but if you're looking to keep a phone for the long haul, the picture changes.
Sony and Huawei phones developed the most faults after six years of ownership, out of those surveyed above. OnePlus, Realme and Google developed the least, with just 11% seeing faults within six years. With Oppo releasing five handsets in the last year, they might be a brand worth considering. Realme doesn't release as many, but they're clearly pretty reliable.
Samsung and Apple are the most popular brands on the market, but they are middle of the road among their competitors for the number of faults they develop, with 13% and 15% in six years, respectively.
However, 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.
You can filter our mobile phone reviews by brand, to see how each model in the range scored in our tests.
What are the most common faults in mobile phones?
1. Battery problems (29%)
Without question, the biggest problems affecting smartphones are battery-related. 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 – representing 28% of all faults that were reported.
How to fix it: On the whole, battery life on phones is improving. But if you notice it getting worse, there are some things you can do to help. Most phones have battery saving settings that can make a big difference, you can prevent some apps from running in the background and draining battery power, or keep screen brightness down. We offer more tips in our guide to improving mobile phone battery life.
If this doesn't help and you think your battery is on its last legs, consider buying a replacement battery instead of upgrading the whole handset. Find out more in our guide on mobile phone repair.
2. Slow and sluggish phones (5%)
The second most common fault to develop in phones is experiencing them becoming slow or sluggish over time.
How to fix it: The easiest way to stop this is to restart your phone every few days to clear the memory and any apps that are running in the background. Also, avoid installing lots of apps and uninstall any you don't use. You should also install software updates regularly and as soon as they're available – as well as important security patches and bug fixes, these often include optimisations to help your phone run more smoothly.
3. Phone freezes (5%)
The third most common fault from our survey is phones freezing, though the chances are still pretty low with only 6% of smartphone owners experiencing this.
How to fix it: If this happens, force a restart according to the manufacturer's instructions. If it keeps happening, try freeing up some of your phone's storage by deleting apps, pictures and videos you don't want to keep. Or add a micro-SD card to expand the memory on your phone (if your phone is compatible with one). If this doesn't work, you may need to factory reset your phone as a last resort.
4. Device crashing (4%)
Only 6% of respondents had their smartphone crash.
How to fix it: Similar to when your phone feels slow, try restarting your phone and uninstall apps you don't need. Make sure apps are regularly updated too. You can turn on auto-update in the app store so you don't have to check if updates are available manually.
5. Software update problems (3%)
Some 3% of faults were attributed to software update problems.
How to fix it: Often, phones can struggle with software updates if there is insufficient storage space on your device. Delete apps, photos and videos that you don't need (or uploading them to the cloud) can help. You can also clear the cache to give your phone room to breathe. It's best to keep your phone charging while it updates and make sure you have a stable internet connection.
Looking to save money? See what's on offer in the best iPhone deals and best mobile phone sales.
Which faults aren't as common?
Worried about losing your fingerprint or face recognition problems? Our survey data suggests there's no reason to be with less than 1% reporting these problems. 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%.
Find out the full survey results including customer satisfaction scores and more in our guide on which mobile phone brand to buy.
What else should I consider when buying a mobile phone?
With just 15% of smartphones developing faults across six years, Which? data suggests we could be keeping our phones for a lot longer than most phone contracts. However, though the hardware may last, most of the time important security updates are not given to smartphones for long enough to keep using them safely.
Security updates are important to help prevent hackers exploiting vulnerabilities in a phone's software. The longer a phone is without security patches, the higher the risk becomes. 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. Find out when your phone is expected to lose security updates in our guide to mobile phone security.
With fault counts being so low for smartphones, buying an older, second-hand phone could save you money on your next handset with little compromise. Just make sure you choose one of the strongest smartphone brands above for a reduced risk of developing faults, and a brand with a good security support period. Find out more in our guide to buying a second-hand phone.
Which? surveyed over 15,000 Which? members and members of the public in March 2025 about their experience with tech products, so we can help you choose which brands to buy. Find out about the best brands for mobile phones, laptops and more in our guides below.
