4 Most Important Updates Coming to watchOS 4

At WWDC 2017, Apple previewed watchOS 4 to developers. At their fall keynote, Apple put an official release date on the new OS (Sept. 19), and even found time to debut a few new features. Use the right arrow to learn about the most important updates and new features coming to watchOS 4.
4 Fitness Updates
The Apple Watch is the number one watch in the world, and one of the best fitness trackers on the market, so it's no surprise that the most notable updates to watchOS are in workout and activity tracking. With watchOS 4, Apple is adding in "smart activity coaching" which will help motivate Apple Watch owners to reach their move, calorie, and stand goals.
With watchOS 4, you will will receive updates through the day, encouraging you to keep a streak going or an evening suggestion of an activity that will help you close your rings. Every month, Apple Watch will also offer up personalized challenges, based on the past month's activity, to push your fitness to the next level.
watchOS 4 also includes a redesigned Workout app, which offers quicker access to your most common workouts, and larger cards for easier, more accurate touching. Apple also added a quick switch feature to the Workout app which enables you to switch from one activity to another without needing to stop the first, then start the second. Simply tap "add workout" and select the type, and the workout tracking adjusts accordingly.
New workouts have also been added to the Workout app, including tracking for High Intensity Interval Training (HIIT) workouts, which uses heart rate and motion to track your workout more accurately than before. Swimmers also get some love in watchOS 4 with automatic split timing, and more detailed distance measurement.
If you're lucky enough to workout at the most updated of fitness facilities, the Apple Watch can now also sync with various fitness equipment. Communicating with the exercise equipment allows your Apple Watch to get additional workout information like incline, resistance, or speed for various activities.
3 New Watch Faces
Another big change to watchOS is the Watch faces. In watchOS 4, Apple is adding to their Disney-themed faces with a trio of characters from Toy Story. Now in addition to Micky and Minnie Mouse, you can also have a fun, interactive Woody, Jessie, or Buzz Lightyear to greet you whenever you check the time.
The new Siri face in watchOS 4 is more than just a shortcut to the virtual assistant. Using Apple's "proactive" AI, the Siri watch face will provide you with timely information like traffic and news, and can also remind you about upcoming calendar events, or give you a little nudge toward closing your fitness rings.
The final big watch face addition in watchOS 4 is the kaleidoscope face. Using any image from your iPhone, you can create a unique, custom kaleidoscope behind the hands of your clock. Throughout the day, the kaleidoscope will change, and rolling the Digital Crown can scroll through the effects, as well.
In watchOS 4, Apple also added a few new complications. The main complications coming in the update are a Siri button for touchscreen access to the digital assistant, and a new, real-time heart rate complication.
2 Apple Watch-ing Your Heart
In addition to the new heart rate watch complication, Apple is significantly improving the heart rate app on Apple Watch. During the keynote, COO Jeff Williams showed off the impressive data that Apple Watch can now show you about your resting and recovery heart rate, both of which can be helpful in understanding your fitness improvements. Additionally, in watchOS 4, Apple Watch can alert you to an abnormally high heart rate during an inactive period, in real time, which can be a sign of a medical condition that may have otherwise gone undetected.
Apple is also partnering with Stanford University and the FDA for heart rhythm research, helping to detect atrial fibrillation and other irregular heart rhythms through a program they are calling the Apple Heart Study. This could likely lead to the Apple Watch being a non-invasive screening tool for various heart conditions.
1 Updated Music App
The final major announcement in regards to watchOS was with the Music app. In a future watchOS 4 update (coming soon, according to Apple) you can expect the Apple Watch to gain full Apple Music support. Whether you are connected via Wi-Fi or cellular, the updated Music app will allow music to play directly from Apple Music to your Apple Watch without downloading the music to your watch first.
Paired with the new cellular Apple Watch, full Apple Music support means you can stream "over 40 million songs", whether you brought your iPhone or not, and makes the Apple Watch an even more impressive fitness companion.
The new Music app in watchOS 4 will also automatically sync your most listened to music, as well as your curated playlists from Apple Music. Using Apple Music data, Apple Watch knows what you listen to most and keeps it ready, allowing you to listen even when you're offline or away from your iPhone.
watchOS 4 Availability
watchOS 4 will be available for all Apple Watch models (1st generation Apple Watch, Apple Watch Series 1, Apple Watch Series 2) on September 19, via an OTA software update, and will ship on Apple Watch Series 3. Registered developers can also pick up the "Golden Master" right now in the developer portal.