The SquareTrade study, released on Saturday, looked at more than 15,000 handsets that were covered by the company's policies. It found iPhones had a malfunction rate of 5.6 percent in the first year, compared to 11.9 percent for BlackBerry smartphones. Palm's Treos fared even worse, with 16.2 percent having some sort of malfunction in the first 12 months of use.
Figures from the analyst firm Canalysys, released last week, showed Apple has now overtaken RIM in the global smartphone sales stakes.
SquareTrade had to project their figures for the iPhone's failure rate over a two-year period, as the handset has not been available for that long — nonetheless, that rate came in at between nine to 11 percent. The equivalent failure rate for BlackBerry handsets was 14.3 percent, with the Treo coming in at 21 percent.
Breaking the figures down, the most prominent malfunctions for iPhone users appear to be touchscreen-related, accounting for a third of all reported issues with that handset. However, 12 percent of iPhone users reported accidental damage to their handsets within the first year of use — the average for other handsets is nine percent.
"It's likely that any iPhone owner can guess the reason iPhone accidents are so common," the authors wrote. "After two minutes of handling an iPhone, it's impossible to escape noticing that the handsets are incredibly slippery. The form doesn't help, either. The dimensions make for a difficult grip, especially for those with small hands. These two factors conspire to make the iPhone more accident prone than just about any other handset model we've seen."
The report's authors also noted that fewer than half-a-percent of iPhone owners reported battery problems after a year of use, compared with around one percent for BlackBerry and Treo users.
SquareTrade's study did not take into account software issues handled directly by the retailer or fixed by firmware updates.
ZDNet UK has requested comment on SquareTrade's report from both RIM and Apple, but had not received it at the time of writing.