Many users, particularly on social media, are complaining about their iPhone 15 Pro or 15 Pro Max overheating. Given the high purchase price, their annoyance is understandable. We therefore wanted to understand where this phenomenon might be coming from and possibly find some solutions.

A problem that arose with the iPhone 15 series

This observation of iPhone overheating occurred in autumn 2023, just a few weeks after the release of the 15 series, and only affects the latter. The 14 series and earlier models are apparently not affected.

Users noticed that their iPhone 15 Pro or 15 Pro Max models were suddenly and frequently becoming very hot, making them uncomfortable to hold.

Apple Alerted to the problem, Apple released an update with iOS 17, suggesting that it was a software issue rather than a manufacturing defect. However, the update was not enough to resolve the problem, and user discontent continues to this day...

Manufacturing defect, software problem... what is the cause of the overheating?

Apple defended itself by citing a problem with third-party application software (downloaded by users). As the update did not change anything, no other explanation was given by Apple.

However, there are several possible explanations for this phenomenon.

The first relates to the titanium used in the chassis of the iPhone 15 Pro and Pro Max. This material replaced the aluminium used in the chassis of the 14 series and earlier models. Titanium is less effective than aluminium at dispersing heat. This could therefore explain the overheating in the iPhone 15 Pro and Pro Max. However, Samsung also turned to titanium for the S24 series, without any overheating issues being reported by users. Either the problem lies elsewhere, or Samsung has been able to compensate for the device's heat dispersion in other ways.

The second potential explanation could also come in part from 5G. Connectivity consumes much more than 4G and therefore requires more energy from the iPhone, which would cause it to heat up more. Combined with the titanium chassis, which disperses less heat, we are beginning to see a possible solution.

The final explanation, given by Apple, comes from third-party applications, i.e. applications downloaded by the user (or applications already present on the iPhone). These applications would require more and more energy from our iPhones, which would explain the overheating. However, many users have suggested that the overheating occurs during phone calls via the Phone application or when using the Camera application. This calls Apple's claims into question.

The mystery therefore remains largely unsolved.

What solutions are there to prevent the iPhone from overheating?

As a user, unfortunately there is no miracle solution. You can always spare your phone from energy-intensive use to prevent the overheating problem from getting worse. To do this, remember to close your apps, avoid spending too much time on energy-intensive apps, etc.

Some users have shared a tip to help combat overheating. All you need to do is delete the contents of your device and then perform a full restore. Be careful, remember to back up your iPhone if you want to try this! There is no guarantee that your iPhone will not overheat after this procedure, but it is one option.

Finally, despite their silence, Apple seems to be aware of the phenomenon, as some internal sources have revealed that a more efficient cooling system is being studied for the design of the iPhone 16 series. Among the options being considered is graphene (a material) to replace certain components. Graphene is four times more effective at dispersing heat than copper. Several of Apple's competitors, such as Samsung and Huawei, have already been using it for years. The problem is that it is a very expensive material, which could therefore have an impact on the retail price. Another option being considered by Apple is a metal casing for the batteries in the Pro versions (which consume more energy than the entry-level model).

All that remains is to wait for the release of the Series 16 in the autumn to study the design changes and user feedback to see whether or not this overheating phenomenon will be limited to the Series 15.