Which? had said they had tested nine iPhone models and it discovered that all of the units fell short of Apple's advertised battery life claim between 18% to 51%. The iPhone XR in particular had the worst results. Apple claims that the XR is capable of a talk time of 25 hours. Which? 's tests state the battery only lasts for a maximum of 16 hours and 32 minutes, a 51% discrepancy.
"With mobile phones now an essential part of everyday life, we should be able to count on our handsets living up to the manufacturer’s claims,” said Natalie Hitchins, Head of Home Products and Services at Which? “There are clearly questions here around how long some mobile phone batteries will last and so it’s important to make sure you find an independent source of reliable information when buying your next phone."
Apple countered claims with a statement, “We rigorously test our products and stand behind our battery life claims. With tight integration between hardware and software, iPhone is engineered to intelligently manage power usage to maximize battery life. Our testing methodology reflects that intelligence. Which? haven’t shared their methodology with us so we can’t compare their results to ours. We share our methodology for testing which we publish in detail here."
However Apple's statement may fall short since Which? has publicly shared their testing methods.
To complete its testing Which? charges up brand new, independently purchased phones to full battery and times how long they last when making continuous calls. It also puts smartphones through a number of different tests before making a ruling on battery life. Which? does the same test to see how long phones last when browsing the internet non-stop before they run out of battery.
Which? also looked at other manufacturers. There were also discrepancies found when looking at HTC’s battery life claims. HTC gave an average talk time of 20.5 hours, although the average time achieved in Which? tests (19.6 hours) was five percent lower.
Nokia, Samsung and Sony also had discrepancies but in stark contrast, they all underestimated talk time when compared to Which? tests. In particular, Sony devices achieved a talk time in Which? tests that was 21 per cent higher than the manufacturer claimed – 16 hours rather than 12.6 hours. Sony’s Xperia Z5 Compact delivered nine hours of extra talk time. While Sony claimed that this model would last 17 hours, Which? found it actually lasted 25 hours and 52 minutes.