The UK is sweltering this week, with temperatures soaring to a record 36C – and it’s not just humans who are struggling. Apple has issued an urgent warning that iPhones can be permanently damaged by the heat, triggering a cascade of safety measures that slow the device to a crawl.
According to Apple, iPhones are designed to operate in ambient temperatures between 0 and 35C. Once the mercury climbs past that upper limit, the phone’s internal safeguards kick in to protect its components and battery. Users will notice the screen dimming permanently, the camera flash ceasing to work, and a ‘Charging on hold’ message appearing on the lock screen, with the note ‘charging will resume when the iPhone returns to a normal temperature’.
“Apple warns iPhone users in UK heatwave that 36C temperatures can permanently damage batteries and trigger safety shutdowns.”
The performance drops dramatically: the device throttles back, cellular and Wi‑Fi signals weaken, and graphics‑heavy apps struggle. If you’re using navigation, the screen may shut off with the warning ‘Temperature: iPhone needs to cool down’ – though audio turn‑by‑turn directions will continue.
But the most serious risk is to the battery itself. Apple states: “Using an iOS device in very hot conditions can permanently shorten battery life.” This reduction in capacity is intended to protect internal components, but it means the battery degradation is irreversible.
Direct sunlight is a quick way to trigger these problems, but with UK temperatures hitting unprecedented levels, Apple warns that iPhones can become vulnerable even indoors. If the temperature warning screen appears, Apple advises: “To resume use of your device as quickly as possible, turn it off, move it to a cooler environment, and allow it to cool down.”