With three million snapped up in its first four days on sale, the new iPad is the hottest gadget around.
For some customers, however, that's been a big problem.
An influential US consumer watchdog is investigating online reports that Apple's tablet computer generates too much heat.
One disgruntled customer said they were returning theirs after it reached temperatures of 47c following only ten minutes of use.
Dutch technology website Tweakers said the new iPad, which went on sale last Friday, was 5c hotter than its predecessor when running.
Customers have complained that the gadget is "too hot to hold", particularly when playing games, prompting a spokesman for the U.S. watchdog Consumer Reports to announce it was conducting its own "scientific analysis with thermal imaging".
It found that the product became "significantly hotter" after playing the popular game Infinity Blade II, with temperatures of 47c recorded on the device's front and back.
However, tester Donna Tapellini said the gadget was "not especially uncomfortable if held for a brief period".
One user of Apple's official support website said: "I think we all know what we have to do - which is to return the iPad. They simply did not do a good enough job - maybe next year."
A spokesman for Apple said the new iPad's performance was "well within our thermal specifications", adding that concerned customers should contact the company.
The launch of the iPhone 4 in 2010 was also troubled, with buyers complaining that the handset could not connect to the internet or make calls if held in a certain way.
- Daily Mail