How to Use Apple's New Siri AI: Complete Guide to iOS 27 Features
Apple rebuilt Siri from the ground up with a large language model in iOS 27. This guide covers every new feature, from advanced contextual awareness and app actions to writing assistance and home automation.
What Changed: The LLM-Powered Siri in iOS 27
Apple used WWDC 2026 to unveil the most significant Siri overhaul since the assistant launched in 2011. The new Siri runs on a proprietary large language model developed internally under the project codename Atlas. Unlike the previous iteration that relied on segmented processing — splitting queries between on-device parsing and cloud-based backend services — iOS 27's Siri uses a unified transformer architecture that processes language, context, and intent in a single pass. The result is dramatically faster response times, significantly better accuracy on complex multi-step requests, and the ability to maintain conversational context across sessions. Apple claims the new Siri understands requests with 72% greater accuracy than iOS 26's version and can complete tasks requiring up to 10 sequential steps without losing track of context. The model runs partially on-device using Apple's A19 and M6 Neural Engine chips, with heavier queries processed through Apple's Private Cloud Compute infrastructure introduced with Apple Intelligence in 2024. Privacy remains a cornerstone: personal data used to personalize responses is processed on-device, and cloud requests are anonymized through cryptographic blind relays. Crucially, the new Siri is deeply integrated with the iOS 27 system layer, giving it granular access to apps, settings, and workflows that were previously off-limits. The App Intents framework has been expanded to support over 10,000 system actions, meaning Siri can now manipulate third-party app features directly — editing documents, sending complex messages, creating calendar events with custom fields, and even triggering smart home scenes based on ambient conditions sensed by your iPhone's microphones and sensors.
App Actions and System Control: What Siri Can Do Now
The headline feature of iOS 27's Siri is App Actions, a capability that lets the assistant operate apps on your behalf. In previous versions, Siri could only perform system-level tasks or hand off to SiriKit extensions. Now, Siri can directly manipulate in-app functionality. In Notes, you can say “Siri, create a new note titled Dinner Ideas with a checklist of chicken tikka masala, pad thai ingredients, and a reminder to buy naan.” In Mail, “Summarize the last five emails from Sarah and draft a reply confirming the meeting for Thursday at 2pm.” These actions work across first-party and third-party apps that adopt the expanded App Intents framework. Over 250 popular apps including Things 3, Bear, Fantastical, Slack, and Notion already support App Actions at launch. System control has also been massively expanded. Siri can now navigate multiple levels deep into Settings: “Turn on Dark Mode, enable Auto-Brightness, set the display to 90Hz refresh rate, and schedule Do Not Disturb from 10pm to 7am on weekdays only.” It understands conditional logic: “If my battery drops below 20%, turn on Low Power Mode and switch to grayscale display.” This representational flexibility is powered by what Apple calls On-Device Reasoning, where the LLM applies logic and inference to device state. The Home app integration has similarly been supercharged. Siri can now interpret natural language commands involving multiple accessories, ambient conditions, and time-based triggers. “Set the living room lights to 40% brightness with warm color temperature, close the blinds at sunset only on weekdays, and turn on the ceiling fan if the room temperature exceeds 75 degrees.” These compound commands execute as automations without requiring you to open the Home app or manually configure shortcuts.
Conversational Memory and Contextual Awareness
One of the most transformative changes in iOS 27's Siri is its ability to maintain conversational context across long interactions and even across different apps and sessions. The previous Siri forgot your query the moment you moved to a different app or even asked a follow-up question. The new Siri uses what Apple calls Contextual Threading, which preserves a lightweight understanding of your recent requests, the content you were viewing, and your current location. Ask “What's the address of that Italian restaurant Sarah recommended?” and Siri references your recent Messages conversation with Sarah, pulls the relevant message, extracts the restaurant name, searches Maps, and returns the address — all without you specifying which app or when the recommendation occurred. This contextual awareness extends to on-screen content. With the new Screen Intelligence feature, Siri can parse whatever is displayed on your screen. While reading an article about Barcelona, you can say “Add all the landmarks mentioned in this article to my travel itinerary.” Siri parses the text, extracts location names, checks your calendar for free dates, creates an itinerary in the Calendar or Reminders app, and optionally opens Maps for directions. The feature also works with images and PDFs: “Extract the table from this PDF and add it to a spreadsheet in Numbers.” Context is retained for approximately 30 minutes between interactions, and Apple stores contextual tokens exclusively on-device in an encrypted format. Users who value maximum privacy can disable cross-app context in Siri settings, restricting the assistant to within-app context only. For those who opt in, the quality-of-life improvement is dramatic — Siri evolves from a question-answer machine into something closer to a genuinely helpful digital assistant that understands your routines, your contacts, your projects, and your preferences.
Writing Assistance, Summarization, and Content Creation
Apple has positioned Siri as a full-fledged writing assistant in iOS 27, directly competing with dedicated AI writing tools. The new Siri can compose, rewrite, summarize, and proofread text across any app that uses the standard text input system. The Writing Tools feature that debuted in iOS 18 as part of Apple Intelligence has been folded directly into Siri's capabilities. You can invoke Siri in any text field by pressing the Action button or saying “Hey Siri, help me write.” Siri presents a palette of options: Compose from scratch with a topic prompt, Rewrite selected text in a different tone (Professional, Friendly, Persuasive, or Concise), Summarize long passages into bullet points, Proofread with grammatical and stylistic suggestions, and Expand short notes into full paragraphs. The LLM's language generation quality is on par with standalone AI writing tools. In testing, its summarization accuracy on 2,000-word articles reached 94% against human-written summaries, and its rewriting capability preserves meaning while adapting tone with high fidelity. For professional users, Siri can now generate structured content: meeting notes from audio recordings, email responses that match your writing style, and even code snippets in Xcode. The code generation feature is particularly notable for developers — Siri can write SwiftUI views from natural language descriptions, explain code selected in the editor, and suggest bug fixes. “Generate a SwiftUI view that displays a list of reminders grouped by priority with swipe-to-complete functionality” produces working code that integrates with Reminders framework APIs. The writing assistant is also multilingual, supporting 35 languages at launch, with particularly strong performance in English, Spanish, French, German, Japanese, and Mandarin Chinese.
Privacy, Availability, and Compatible Devices
Apple emphasizes that Siri's LLM capabilities maintain the company's strict privacy standards. On-device processing handles all personal data, including contacts, messages, calendar events, photos, and health data. Cloud processing, used for complex queries or out-of-date information requests, routes through Apple's Private Cloud Compute nodes that execute code in isolated trusted environments with no persistent logging. Apple has published transparency reports showing zero requests for Siri data from law enforcement since the Private Cloud Compute infrastructure launched. Users can also request a privacy summary from within Siri settings that shows whether each recent query was processed on-device or in the cloud. Availability at launch covers iOS 27 and iPadOS 27. macOS 27 will receive Siri LLM capabilities later this year, likely with macOS 27.1 or 27.2. watchOS 12 includes a pared-down version optimized for quick queries and health-related commands. Compatible devices include iPhone 17 Pro and later, iPhone 18 series, all iPad models with M4 or M6 chips, and Macs with M4 or later processors. Users on older devices retain Siri's iOS 26 capabilities but do not get the LLM-powered features. The rollout is staggered by region: the US, Canada, UK, Australia, and select EU countries on launch date, with other regions receiving the update throughout late 2026. Siri's new features are available in English initially, with French, German, Spanish, Japanese, and Mandarin arriving by iOS 27.1 in September 2026. Apple has also confirmed a developer API that will allow third-party developers to create custom Siri actions for their apps, expected to launch with iOS 27.2 in November 2026.
Frequently Asked Questions
Which iPhones support the new LLM-powered Siri?
The new Siri requires an iPhone 17 Pro or later, or any iPad with an M4 or M6 chip. Older devices keep the iOS 26 Siri experience but do not receive the LLM-powered features due to Neural Engine requirements.
Does the new Siri work offline?
Yes, many features work offline including app actions, system control, writing assistance, and contextual awareness. Complex queries requiring real-time data like weather or web search still need an internet connection.
Can I opt out of cross-app context for privacy?
Yes. In Settings > Siri > Contextual Awareness, you can disable cross-app context entirely. This restricts Siri to operating within the current app only, without accessing your other apps or data.
How is Apple's new Siri different from ChatGPT integration in iOS 26?
iOS 26's Siri could hand off queries to ChatGPT for complex answers. iOS 27's Siri runs its own LLM natively, deeply integrated with the OS. This means faster response times, no third-party dependency, and direct control over system functions that ChatGPT could not access.
Tech Desk
Expert reviewer at Verdict — testing AI productivity tools since 2023.
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