Apple’s iOS 27 update, announced Thursday at the company’s Worldwide Developers Conference in Cupertino, is shaping up as the most significant iPhone software revision since the introduction of the App Store, with more than 250 user-facing changes covering everything from the home screen to how the phone handles calls, messages, and AI-assisted tasks.

The headline addition is a thoroughly rebuilt Siri. The previous version had long been criticised for failing to hold context between questions and for struggling with anything beyond simple commands. The new Siri can carry multi-turn conversations, understand context from earlier in the same session, and complete complex tasks across multiple apps simultaneously. Apple described it as Siri finally capable of being genuinely useful rather than frustrating.

The home screen is getting its most substantial redesign since the original iPhone. Users will be able to resize icons freely, place widgets anywhere on the grid, and create fully custom layouts that break from the rigid icon-per-slot structure that has defined the iOS home screen for eighteen years. A new tinting system lets users apply a single colour palette across all icons and system elements at once.

On-device AI is the engine running most of the new features. Apple’s third-generation Foundation Models, which power iOS 27, are significantly faster and more capable than the version that shipped with iOS 26. They run entirely locally on the device’s Neural Engine, meaning the AI processing happens without sending data to Apple servers. The company has staked much of its privacy positioning on this distinction from competitors whose AI features route queries through cloud infrastructure.

The update also expands what third-party developers can do with Apple Intelligence. New APIs give app developers access to the on-device language models for summarisation, classification, and content generation tasks. That opens the door to a new generation of productivity apps that will be built ahead of the September launch, which Apple confirmed is on schedule alongside new iPhone hardware.

The camera system in iOS 27 includes a new computational photography pipeline that Apple says produces noticeably better results in low light and at high zoom. These improvements are partly hardware-dependent and will perform better on the latest generation of devices, though Apple confirmed the full iOS 27 update is free for all supported iPhones going back to the iPhone 14 series.

Messaging and FaceTime are also substantially updated. The iMessage app gets a persistent chat thread that automatically surfaces relevant past conversations when a new message arrives. FaceTime adds real-time translation, a feature that competes directly with what earlier previews had suggested was coming. The update also introduces background noise cancellation in FaceTime calls that Apple says outperforms existing third-party solutions.

Privacy controls are tighter across the system. Apps now require explicit per-session permission to access location rather than persistent background access, and a new Privacy Dashboard gives users a single view of which apps have accessed sensors, contacts, or location in the past seven days. The dashboard surfaces requests in plain language rather than technical permission categories.

Apple confirmed iOS 27 will be available as a free over-the-air update in September, timed with its next iPhone launch. Developer and public betas begin rolling out next week. The full WWDC session library covering every iOS 27 API is available to registered developers starting today. The competitive AI assistant landscape iOS 27 is entering is shaped partly by policy decisions at rivals, including Anthropic’s Claude, whose research access reversal this week signals a more open approach to external scrutiny. Apple’s new camera pipeline draws on sensor technology whose professional-grade equivalent is covered in recent analysis of the Sony A7R VI.