Apple iOS 27 beta 4 released with Siri AI focus and major performance upgrades

Apple has rolled out the fourth developer beta of iOS 27 (build 24A5390f), alongside beta releases for iPadOS 27, macOS 27 Golden Gate, watchOS 27 and tvOS 27. The update refines the user interface, fixes bugs, and emphasizes the integration of the rebuilt Siri AI, which can now understand screen context and personal data. The AI features are not yet available on Chinese iPhones, where Apple is testing integration with Alibaba’s Qianwen model, and are blocked in the European Union due to Digital Markets Act concerns.

Apple also published Release Candidates for iOS 26.6, iPadOS 26.6 and macOS 26.6, signalling the final stage before public launch. Performance claims include up to 30 % faster app launches, 70 % quicker photo loading, and up to 80 % faster AirDrop transfers, along with broader speed gains across Safari, Mail, Health and HomeKit. Siri AI on watchOS 27 has been seeded for developers, adding new gesture controls and dynamic app grid features.

Hardware‑specific notes indicate that the most advanced Apple Intelligence and Siri AI functions will run only on newer devices (iPhone 15 Pro and later, Apple Watch Series 9/10 and Ultra 2/3). Older compatible models will receive the OS update without the AI enhancements.