Apple may not be ready to confirm that the iPhone 3GS has an overheating issue, but they have posted advice on keeping the iPhone 3GS and iPhone 3G within acceptable operating temperatures. This advice includes not leaving the iPhone in the car or exposing it to direct sunlight for extended periods of time.
DS60xxFT-M series is designed for medium-range indoor and outdoor monitoring and temperature measurement. The DS60xxFT-M series features 24- hour monitoring, sharp images and highly accurate temperature measurement in harsh weather conditions.