Developer StephenDev0 shared results of a performance test for GTA V on September 27 through the X account of his project, Vapor. The test was run on an iPhone 18 Pro Max and showed that the PC version of the game runs at an average of 66 frames per second during a city driving sequence. This performance is comparable to a GeForce GTX 1650, an entry-level graphics card from 2019. The test was conducted in 1080p resolution using DirectX 11, with high textures, FXAA anti-aliasing, and anisotropic filtering set to 16x. The chip’s performance per watt is 1180% higher than that of the GTX 1650, which uses up to 75 watts of power. In contrast, on the iPhone 17 Pro Max, GTA V ran at around 20 frames per second using XeniOS, an Xbox 360 emulator. However, the two tests are not directly comparable because the game versions and software differ. The A20 Pro chip in the iPhone 18 Pro Max benefits from Apple's improved cooling system. Since the iPhone 15 Pro in 2023, Apple has aimed to make its devices more capable gaming platforms. However, without a fan, smartphones can overheat and throttle performance. The iPhone 18 Pro addresses this with the A20 Pro chip, which is etched in 2 nanometers, allowing more transistors in a smaller space and using less power. It also features a new packaging method called WMCM, which improves heat distribution, and a larger vapor chamber for better cooling. YouTuber Dame Tech tested the performance improvements of the iPhone 18 Pro Max against the iPhone 17 Pro Max using two games. On Resident Evil 4 Remake, the A20 Pro achieved an average of 58 frames per second, while the A19 Pro reached 38.6, a 50% difference. Apple had previously claimed a 40% improvement in graphics performance. In the slowest parts of the game, the A20 Pro showed a 77% improvement, indicating better heat management. However, on Assassin’s Creed Mirage, which is capped at 30 frames per second, the performance gap was smaller, at 18.6%. Vapor is not yet available for download. StephenDev0 is known for StikDebug, a tool that allows just-in-time (JIT) compilation on iPhones. This technique translates code as it runs, which is essential for emulators. iOS typically blocks this for third-party apps. StephenDev0 announced Vapor on September 12, aiming to run PC and Mac games on iPhones, iPads, and Apple TVs, starting with iOS 17.4. He notes that GTA V is still "a work in progress" and has some unresolved issues. On Android, similar capabilities exist, with apps like Winlator running PC games on Qualcomm chips. Qualcomm recently unveiled the Snapdragon 8 Elite Gen 6, including an "Extreme" version. Vapor will launch alongside StikStore, an alternative app store created by the same developer to bypass the App Store.