watchOS is the operating system of the Apple Watch, created and developed by Apple. It is based on iOS, the operating system used by the iPhone, and has many similar features. Its original version was released on April 24, 2015, along with the Apple Watch, the only device that runs watchOS. watchOS exposes an API called WatchKit for developer use.
Interface overview The home screen, rendered by and also known as "Carousel", consists of circular application icons that can be launched by touching the display, which allows users to access their favorite apps.
Prior to watchOS 3, "Glances" offered quick access to summaries of the most frequently used native and third-party applications. The Glances view was opened with a swipe-up gesture from the watch face screen. In watchOS 3, Glances were replaced with a redesigned Control Center that mirrors the functionality seen in iOS, providing a more unified experience across Apple devices. The Control Center is accessed with a swipe-up gesture from the watch face screen. Additionally, the friends menu, previously activated with the side button, was repurposed as a dedicated dock for apps, enhancing multitasking and app management.
Prior to watchOS 7, different actions and options appeared depending on whether the user taps or deep-presses, detected with the pressure-sensitive (Force Touch) Display. Force Touch was completely removed in watchOS 7, and all actions requiring the feature were moved to specific options in the Settings app or to long-press actions. With the launch of watchOS 7, Force Touch technology was phased out. This feature was replaced by additional options in the Settings app and extended press gestures to accommodate all necessary interactions, making it more consistent with other Apple devices that do not support Force Touch.
Supported health metrics Since its inception, watchOS has supported an increasing number and variety of health metrics for measurement and tracking. These include: heart rate maximal aerobic capacity, otherwise known as VO2 max. (added in watchOS 4, enhanced in watchOS 7) electrocardiogram, otherwise known as EKG or ECG (added in watchOS 5.1.2) blood oxygen saturation, otherwise known as SpO2 (added in watchOS 7) menstrual cycle status (added in watchOS 6) sleep duration & respiratory rate tracking (added in watchOS 7) body temperature tracking (added in watchOS 9) sleep apnea detection (added in watchOS 11)
HealthKit
For several years, Apple has been developing its HealthKit product in an attempt to penetrate the lucrative healthcare and wellness industry, which CB Insights believe holds a huge growth opportunity for Apple. This was confirmed by Jony Ive, Apple's former chief designer, in an interview. He said that health was a crucial element in the Apple Watch since the day of its inception and that the developmental trajectory of the hardware and the watchOS were geared towards health-based capabilities. Ive pointed out that one of the primary apps that shipped with the first watchOS allowed users to track and communicate as well as encourage them to move, exercise, and stand. He said:Many of us have our phones with us all the time, but they aren't connected to you. Imagine having something this powerful with you at all times, and what opportunities that might present to the user. The opportunity is phenomenal. Particularly when [you] don't understand just where we are today in terms of technology and capability, but where we are headed.Applications have been developed for watchOS that not only keep users active but also diagnose illnesses. For example, the app called DeepHeart, a deep-learning network that can detect atrial fibrillation, hypertension, sleep apnea, and diabetes. It taps into the HealthKit platform to collect data, particularly those collected by the Apple Watch's heart sensor.
Version history Overview
+ Overview of watchOS versions Version Initial release date Latest version Latest release date Device end-of-life SE Series Ultra iPhone watchOS 1 rowspan="3" colspan="3" rowspan=2 watchOS 2 watchOS 3 5, 5C watchOS 4 0 watchOS 5 colspan="3" 5S, 6 watchOS 6 1, 2 watchOS 7 colspan="3" watchOS 8 3 6S, SE (1st), 7 watchOS 9 colspan="3" 8, X watchOS 10 1st 4, 5 watchOS 11 colspan="3" XS, XR watchOS 26 2 6, 7, 8 1st watchOS 27 rowspan="2" colspan="4"
watchOS 1 The first version of watchOS 1 was 1.0 and was based on iOS 8.2. The second version of watchOS 1 was 1.0.1 and was based on iOS 8.3. Overview of watchOS 1 versionswatchOS versioniOS version based onBuildFeatures 1.08.212S507Initial release on Apple Watch (1st Generation). UI Free-floating Circular app icons in home screen. Zoom in with Digital Crown. 9 watch faces: Chronograph, Color, Modular, Utility, Mickey Mouse, Simple, Motion, Solar, Astronomy 20 stock apps: Activity, Alarm, Calendar, Camera Remote, Mail, Maps, Messages, Music, Passbook, Phone, Photos, Remote, Settings, Siri, Stocks, Stopwatch, Timer, Weather, Workout, World Clock. 1.0.18.312S632 Display support for new Emoji characters. Notification screen UI tweaks. Improved performance: Free floating Circular app icons in home screen. Zoom in with Digital Crown. Siri. Measuring stand activity. Calculating calories for indoor cycling and rowing workouts. Distance and pace during outdoor walk and run. Accessibility. Third-party apps. Wrist Raise (more sensitive to real-life wrist raises). Additional language support: Brazilian Portuguese, Danish, Dutch, Swedish, Russian, Thai, Turkish. Security fixes
watchOS 2 Overview of watchOS 2 versionswatchOS versioniOS version based onBuildFeatures 2.09.013S344New Watch faces Time-lapse face: Hong Kong, London, Mack Lake, New York, Shanghai, Paris Photo & Photo album faces with support for Live Photos New Time Travel function where you can see both past and future events Nightstand Mode 9 new colors for customization New multicolor Modular face 3rd party apps Complications support
Siri Workout and Maps support FaceTime audio calling and email replying support HomeKit support Added support in following countries: Austria, Belgium, Norway
Activity and Workout Workouts done in 3rd-party apps will be included in Activity rings Sharing support from Activity app on iPhone Interactive achievements Weekly Summary Activity notifications can now be muted for a day Workouts can now be automatically saved
Apple Pay and Wallet Discover cards support Reward cards, store credit and debit cards support Passes can now be added from 3rd party apps
Friends You can now add more than 12 friends to your Watch Groups support Multicolor sketches support Animated emoji support
Maps New Transit view in selected cities List of directions can now be shown Station placards support with departure information
Music New Beats 1 Radio support New Quick Play button for Apple Music
Miscellaneous You can now reply to emails right from your Watch using dictation, emoji, or smart replies Support for FaceTime audio calls Support for Wi-Fi calling Activation Lock – No one can activate an Apple Watch without a proper Apple ID and password New system languages: English (India), Finnish, Indonesian, Norwegian, Polish Dictation support extended to include the following languages: Dutch (Belgium) English (Ireland, Philippines, South Africa) French (Belgium) German (Austria) Spanish (Chile, Colombia) Smart replies support extended to include the following languages: Traditional Chinese (Hong Kong, Taiwan) Danish Dutch English (New Zealand, Singapore) Japanese Korean Swedish Thai
Developer Native SDK support 3rd-party apps can now access the accelerometer, heart rate sensor, microphone, Taptic Engine, and Digital Crown You can now play videos directly on your Watch You can now run apps without your iPhone with a Wi-Fi connection Complications for watch faces support Support for Workouts from 3rd party apps – Metrics will count toward the Activity rings as well as included in the Activity app on iPhone 2.0.19.113S428 New emoji Bug fixes 2.19.213S661 New system languages: Arabic, Czech, Greek, Hebrew, Hungarian, Malay, Portuguese (Portugal), Vietnamese Right-to-left language support In Arabic, switch between Latin and Hindi numerals New Complication for Islamic and Hebrew calendars Siri support extended to include Arabic (Saudi Arabia, United Arab Emirates) Dictation support extended to include the following languages: Arabic (Saudi Arabia, United Arab Emirates) English (Malaysia) Czech Greek Hebrew Hungarian Portuguese (Portugal) Vietnamese Bug fixes 2.29.313V144 You can now pair 2+ Apple Watches to a single iPhone New Nearby function in Maps New system languages: Catalan, Croatian, Slovak, Romanian, Ukrainian Dictation support extended to include the following languages: Catalan Croatian Slovak Romanian Ukrainian English (Saudi Arabia, UAE, and Indonesia) Siri support extended to include Malay, Finnish, and Hebrew Background heart rate measurements have their frequency increased when you're stationary 2.2.19.3.213V420 General performance and stability improvements. 2.2.29.3.313V604 General performance and stability improvements.
watchOS 3 Overview of watchOS 3 versionswatchOS versioniOS version based onBuildFeatures 3.010.014S326 Initial Release on Apple Watch Series 1 (Dual-Core) and Apple Watch Series 2 (Dual-Core)
Navigation Favorite apps in Dock Apps in Dock updates with up-to-date information on launch Dock can contain up to 10 apps Simple switch to different watch face with a swipe Control Center can be toggled with a swipe up
New Watch faces Minnie Mouse face Activity faces Numerals faces Complications support for Photo, Photo Album, Timelapse, and Motion faces New Complications: Workout, Music, and Messages, etc. Face Gallery in Apple Watch app on iPhone 3rd-party Complications support
Activity Share and compare activity rings Activity progress notifications for a person you have shared your activity progress with Smart replies for above notifications New "Sharing" tab on Activity app on iPhone
Workout Quick start Customizable metrics view Gestures support for pausing, resuming, or marking segments Support for "Other" workouts not listed in built-in workout types Auto-pause in running workouts for inactivity Siri support Route maps with a speed indicator (Outdoor workouts only)
For Wheelchairs Activity rings support for people using a wheelchair Pushes now contribute to the move ring Stand ring and "Time to Stand" notification substituted with Roll ring and "Time to Roll" notification Outdoor Run or Walk pace workouts
Breathe app New app for breathing sessions Visualization and haptics indicate when to inhale or exhale Adjustments for session length and amount of breaths per minute Summary with heart rate "Time to Breathe" notifications Weekly Summary
Communication Full-screen effects for celebrations Tap to quick reply Animations for handwritten messages Send built-in or 3rd party stickers Ability to view secret messages Replies now available in Messages and Mail notifications New and redesigned emojis
Scribble Write directly on Apple Watch and it will automatically convert to text Scroll through predictions with Digital Crown Available in English, Simplified Chinese, and Traditional Chinese
Emergency SOS You can now call emergency services by pressing and holding the side button Your SOS contacts will be notified with your location You can also display your Medical ID stored on your Watch Emergency numbers are automatically adjusted per your location
Home New app to control accessories through HomeKit You can now control all your accessories directly from your wrist IP camera support: Watch live video with controls and notifications directly on your Watch
Miscellaneous New Reminders app New Find My Friends app Apple Pay support in 3rd-party apps