Apple has warned users of its latest iPhones that high or low temperatures can lead to problems with the devices.
The company said that extreme temperature conditions might cause problems with the battery and even stop the phones working properly.
And the temperatures are not that extreme. "Operate iPhone 3G and iPhone 3G S in a place where the temperature is between 0º and 35ºC (32º to 95°F). Low- or high-temperature conditions might temporarily shorten battery life or cause the device to temporarily stop working properly," said an Apple update.
Apple also recommends that users store iPhone 3G and iPhone 3GS in a place where the temperature is between -20º and 45ºC. "Don't leave the device in your car, because temperatures in parked cars can exceed this range," it said.
Problems caused to the iPhone when the temperature is high or low include the device stopping charging, the display dimming and a weak signal available.
A temperature warning message will appear when the iPhone is too hot or cold.
PCworld senior editor Tim Moynihan recently tested the resilience of the Apple iPhone 3G using keys, breakfast cereal, water, dish soap, and city streets.
The fridge or Centre Court at Wimbledon this week might have been more of a challenge.