There are 4 sources of mobile heat:
2 are internal: the processor and the battery
2 are external: direct heat from the sun and ambient heat from the environment
Typically, your phone can handle one of these at a time without issue, however combined they pose a grave threat to your phone’s performance and longevity.
For example, navigating with a maps program usually doesn’t cause issue, however when combined with direct sunlight the results are disastrous to your phone’s performance. It is common for a phone to become too laggy to operate on a summer day, or even for it to shut off completely.
Some sources are powerful enough on their own to cause issues. These ‘super-factors’ cause significant damage to your phone’s battery health and performance.Direct sunlight is the most common cause of overheating problems, enough to completely debilitate a phone, even on a relatively cool day.
Another super-factor is the processor at the heart of your phone. Whether you are FaceTiming, playing games, using AR, taking videos, or even scrolling through TikTok, your phone may lag or overheat after only a few minutes. It took only 7 minutes for an iPhone 13 pro to overheat when using an AR application. Common symptoms of an overheating phone include:
The longevity of your phone is directly tied to its thermal state. Exposing your phone to high temperatures permanently damages the battery and reduces longevity. It also permanently affects the performance of your phone. As your battery decays over time, it ‘clogs up’ and cannot deliver the voltages that the CPU requires. As a result, the phone reduces the voltage, and therefore the performance of the CPU, to prevent catastrophic failure. Thus a decayed battery is the most common cause for chronic poor performance in a phone. On iPhones, when the battery decays enough the phone enters a state called Permanent Performant Management in which the symptoms of an overheating phone become permanent. Those symptoms include: