Apple released the first iOS 27.3 beta to developers on Tuesday, opening testing for software updates across iPhone, iPad, and Mac. The build introduces vertical tabs in Safari, expands Siri AI integrations, and brings back a redesigned Health app that Apple previously pulled during earlier testing.
Key points
- Apple seeded the first iOS 27.3 and iPadOS 27.3 developer betas one week after the public release of iOS 27.2.
- Safari receives vertical tabs, adaptive dark mode, and new Siri AI controls across mobile and desktop platforms.
- The overhauled Health app returns with Health Age metrics and lab appointment scheduling through Quest Diagnostics.
- The beta cycle prepares regional expansions, including upcoming Apple Intelligence features scheduled for mainland China.
What changes in Safari
The update brings three visible adjustments to Apple’s default web browser on iPhone, iPad, and Mac. The most notable interface addition is vertical tabs, which shifts the browser tab strip from the top or bottom bar into a side-aligned column. The layout matches tab management styles already common in desktop browsers, giving users a clearer view of open page titles on wider screens and larger mobile displays.
Alongside vertical tabs, Apple added an adaptive dark mode to Safari. The setting alters website colours based on active system preferences and ambient conditions, matching web page backgrounds more closely to dark interface elements even when a site lacks native dark theme styling.
Safari also incorporates deeper Siri AI capabilities within the browser window. While Apple originally previewed an automated tool to detect and fix weak or compromised passwords using Apple Intelligence, early testing shows that specific feature remains absent. Instead, the current build prioritises conversational web lookups and automated page actions tied to the voice assistant.
The return of the redesigned Health app
The primary inclusion for iPhone users in this release cycle is the restored Health interface. Apple first introduced the revised design during the early iOS 27.2 beta cycle before removing it in beta 4. At the time, the company confirmed that the updated design would arrive before the end of the year.
The refreshed layout puts heavier emphasis on Apple Intelligence insights. Daily metrics display automated pattern summaries, highlighting deviations in sleep, resting heart rate, and movement trends over several weeks rather than showing isolated raw numbers.
A core feature in the restored app is Health Age, a metric that calculates biological health indicators against chronological age based on activity, cardiovascular data, and sleep consistency. The update also retains direct booking integration with Quest Diagnostics, allowing users to schedule laboratory blood draws and diagnostic tests directly through the Health app interface without opening a third-party portal.
Siri AI updates and cross-platform changes
The iOS 27.3 beta builds on voice assistant changes that debuted with iOS 27.2 late last month. That earlier release gave Siri AI the ability to recall previous conversational context, such as venues or links the assistant previously surfaced in earlier chats. The new 27.3 build broadens those recall functions into third-party apps, making it easier to pull references across messaging and productivity tools.
The voice assistant also gains tighter integration on Apple Watch, mirroring updates seeded across iPadOS 27.3 and macOS. Apple is using this testing phase to prepare regional software infrastructure, including the Apple Intelligence China rollout that engineers have readied for deployment during this beta window.
Certain announced features are still missing from the first developer preview. Testers reported that reachability adjustments planned for the iPhone Duo hardware have not yet been activated in this build. Apple frequently holds back individual hardware tweaks until secondary or tertiary beta releases once core system stability is established.
Rollout and testing schedule
The release arrives exactly one week after Apple launched iOS 27.2 to the general public on 26 October. That previous update had unified the iPhone Duo with standard iPhone models under a shared version number, introducing Messages suggestions alongside audio and video enhancements across Podcasts and FaceTime.
Registered developers can install the initial test build immediately by navigating to Settings, selecting General, choosing Software Update, and opting into the developer beta channel on their devices. Apple requires an active developer account linked to the Apple ID in use to download the update package over the air.
Apple will run several developer iterations of iOS 27.3 over the coming weeks before seeding public beta versions to general testers. A final public rollout for compatible iPhone models is scheduled to follow later this winter.
