June & July 2023 were the hottest months on record for the planet, at least until August 2023. Among the many ill effects of such heat are what it does to iPhones, iPads, Macs, Apple Watches, and other digital devices. Excessive heat shortens the overall lifespan of lithium-ion batteries and increases the likelihood of both transient errors and hardware failures—iPhones warn you when they’re getting too hot because of these issues. Apple recommends using nearly all its devices in conditions no hotter than 95ºF/35ºC and storing them in locations that don’t exceed 113ºF/45ºC. (The exception is the adventurous Apple Watch Ultra, which can be worn in temperatures up to 130ºF/55ºC.) The most common place to avoid is a car parked in the sunshine on a hot day, which can easily exceed 130ºF within an hour and rise from there. So don’t leave your iPhone in the car during an afternoon at the beach!