Whether or not anecdotal reports of iPhones overheating are true, Apple has taken them seriously enough to reveal the presence of a temperature warning screen for the iPhone 3G and 3GS.
Here's the deal: an unknown but probably very small number of iPhones have been affected by overheating, to the point that some white iPhone 3GSes have allegedly turned pink. Sascha Segan, our phone analyst, said he hasn't seen any such problems with his iPhone 3GS, however.
Apple, however, has issued what some might call a "common sense" warning: a support document that warns users not to keep the iPhone in an environment where temperatures can exceed 113 degrees Fahrenheit, including parked cars.
< A screen shot of the Apple iPhone temperature warning screen. (Source: Apple)
But Apple also warns that CPU-intensive applications, such as playing music or using the GPS while in direct sunlight may also overheat the iPhone.
In that case, actually using the iPhone in temperatures over 95 degrees can also trigger the temperature warning. "Low- or high-temperature conditions might temporarily shorten battery life or cause the device to temporarily stop working properly," Apple warns.
That will prompt the device to trigger the temperature warning above, essentially locking it except for emergency calls.
Obviously, summer temperatures in many locations top 95 degrees. Las Vegas, for example, has forecasts topping 100 degrees for the next 10 days; Phoenix routinely climbs above 103.
Apple also says that the iPhone 3G and 3GS should not be stored where the temperature can fall under -4 degrees Fahrenheit, or used in less in temperatures under 0 degrees F.
If the phone exceeds those temperatures, Apple says, the iPhone may stop charging, its display might dim, a weak cellular signal may be experienced, and the temperature warning screen above may also appear. Apple's support document implies that there's a temperature sensor of some sort built in to the iPhone 3G or 3G S.
If that happens, Apple says, you'll need to let the iPhone cool down before you use it again, although the phone may be able to place emergency calls during that time. How long will the cooldown process take? Apple doesn't say.
