Here are the full release notes for watchOS 8. The software update for Apple Watch is set for release on Monday, September 20.
watchOS 8 brings you new ways to stay healthy, active, and connected. A redesigned Photos app helps you stay connected to your most precious memories, and the new Mindfulness app and new Tai Chi and Pilates workout types will help you lead a healthy and fit life. And updates to Wallet and Home make it simple and convenient to access your house, car, and even the places you love to visit.
Watch Faces
    •    Portraits face uses segmentation data from portrait photos taken on iPhone to create an immersive, multi-layered face (Apple Watch Series 4 and later)
    •    World Time face lets you track the time in 24 different time zones at once (Apple Watch Series 4 and later)
Home
    •    Status and controls for accessories in your home now appear at the top of the Home app
    •    Quick views to see if accessories are on, have a low battery, require a software update, and more
    •    Accessories and scenes dynamically appear based on the time of day and frequency of use
    •    Dedicated camera room for viewing all available HomeKit camera feeds in one place, with support for multiple aspect ratios
    •    Favorites area gives you access to the scenes and accessories that you use most
Wallet
    •    Home keys let you tap to unlock a supported home or apartment door lock
    •    Hotel keys allow you to tap to unlock your room at participating hotels
    •    Office keys allows you to tap to unlock your office doors for participating corporate offices
    •    Car keys with Ultra Wideband on Apple Watch Series 6 let you unlock, lock, and start your supported vehicle as you approach
    •    Remote keyless entry functions on your car keys allow you to lock, unlock, honk your horn, preheat your car, or open your trunk
Workout
    •    New custom algorithms in the Workout app for Tai Chi and Pilates provide accurate tracking of calorie metrics
    •    Automatic Outdoor Cycling workout detection sends a reminder to start the Workout app, giving you retroactive credit for exercise already started
    •    Automatic pause and resume for Outdoor Cycling workouts
    •    Improved accuracy of calorie metrics for Outdoor Cycling workouts while riding an e-bike
    •    Users 13 and under can now track hiking workouts with more accurate metrics
    •    Voice feedback announces workout milestones using the built-in speaker or connected Bluetooth device
Fitness+
    •    Guided Meditations can help you practice meditation, featuring audio sessions on Apple Watch and video sessions on iPhone, iPad, and Apple TV that guide you through specific themes
    •    Pilates workouts are now available, with new workouts every week that are designed to improve strength and flexibility
    •    Support for Picture-in-Picture viewing on iPhone, iPad, and Apple TV, so you can watch your workout while you also view other content in compatible apps
    •    Expanded workout filters for Yoga, Strength, Core, and HIIT workouts, including whether equipment is required
Mindfulness
    •    Mindfulness app includes an enhanced Breathe experience along with a new Reflect session
    •    Breathe sessions have tips that help add a physical connection to deep-breathing practices and a new animation to guide your session
    •    Reflect sessions give you a simple idea to focus your thoughts, along with a visualization that shows the passing of a minute
Sleep
    •    Respiratory rate is measured by Apple Watch during sleep
    •    Ability to review respiratory rate during sleep in the Health app, and be notified if a trend has been detected
Messages
    •    Ability to compose or reply to messages by using Scribble, dictation, and emoji all from the same screen
    •    Ability to adjust dictated text by using the Digital Crown to scroll to where you want to edit
    •    Support for #images in Messages allows you to search for a GIF or select one you’ve used recently
Photos
    •    Redesigned Photos app allows you to view and manage your photo library from your wrist
    •    Highlights from Memories and featured photos, in addition to your favorites, sync to Apple Watch with new content generated daily
    •    Photos from synced Memories will be displayed in a mosaic-style grid, highlighting some of your best shots with a larger photo
    •    Ability to share photos through Messages and Mail
Find My
    •    Find Items app allows you to locate items with an attached AirTag and compatible third-party products with the Find My network
    •    Find Devices app helps you locate your misplaced Apple devices, as well as devices owned by someone in your Family Sharing group
    •    Find My separation alerts notify you if you leave your Apple device, AirTag, or compatible third-party item behind
Weather
    •    Next-hour precipitation notifications alert you when rain or snow is about to start or stop
    •    Severe weather notifications alert you about certain events including tornados, winter storms, flash floods, and more
    •    Precipitation chart that visually depicts the intensity of the rain
Other features and improvements:
    •    Focus lets you automatically filter notifications based on your current activity, such as fitness, sleep, gaming, reading, driving, work, or personal time
    •    Apple Watch automatically aligns with any Focus that you set in iOS, iPadOS or macOS, so you can manage notifications and stay focused
    •    Contacts app gives you the ability to access, share, and edit your contacts
    •    Tips app provides collections of helpful hints and suggestions for how to best use your Apple Watch and its built-in apps
    •    Redesigned Music app allows you to find and listen to music and radio all in one place
    •    Ability to share songs, albums, and playlists in the Music app through Messages and Mail
    •    Support for multiple timers, including Siri support for adding labels to timers
    •    Cycle Tracking can now use heart rate data from Apple Watch to improve predictions
    •    New Memoji stickers to send a shaka, a handwave, a lightbulb moment, and more
    •    Over 40 outfit choices and up to three different colors to customize your Memoji stickers’s clothing and headwear
    •    Real-time measurement of your headphone audio level in Control Center when listening to media
    •    Ability to add transit cards in Wallet for Family Setup users in Hong Kong, Japan, and select cities in China mainland and US
    •    Google account support for Calendar and Mail for Family Setup users
    •    AssistiveTouch allows users with upper limb differences to answer calls, control an onscreen pointer, launch a menu of actions, and more, using hand gestures like a pinch or a clench
    •    Additional larger text size option available in Settings
    •    Support for the ECG app on Apple Watch Series 4 or later in Lithuania
    •    Support for irregular heart rhythm notifications in Lithuania
Some features may not be available for all countries or all areas, for more information visit:
https://www.apple.com/watchos/feature-availability/
For information on the security content of Apple software updates, please visit this website:
https://support.apple.com/kb/HT201222
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