In its release note, Apple stated that iOS 17.0.3 “addresses an issue that may cause iPhone to run warmer than expected.” The iPhone 15 Pro and Pro Max are operating cooler when fast charging as a result of this upgrade, according to ZDNET’s testing using a thermal camera.
The iPhone 15 Pro and iPhone 15 Pro Max could overheat when fast-charging or when running third-party apps like Instagram, Uber, or Asphalt 9, which looked to worsen a bug in the iOS 17 operating system, as has been extensively reported since the release of the iPhone 15 Pro on September 22. The iPhone 15 Pro models incorporated a new titanium frame with an aluminum substructure to replace the stainless steel frame from the previous several pro versions. Apple stated that the overheating issue was attributable to a software bug and was unrelated to the new hardware or design.