Apple seeded the fourth watchOS 9 update to developers for testing three weeks after it was released to developers.
The configuration profile from the Apple Developer Center is required for the installation of watchOS 9. The dedicated Apple Watch app on the iPhone can be used to download watchOS 8 after installation. To update to new software, an Apple Watch needs to have 50 percent battery life, it needs to be placed on the charge, and it needs to be within range of the iPhone.
New watch faces and updates to existing watch faces are included in watchOS 9. A person can now be tracked for how long they've been in atrial fibrillation.
The sleep tracking feature now includes sleep stages and Apple has added a medication app. When it's time to take your medication, you can use theMedications app to keep track of it and remind you.
Improvements and custom workouts are added to the Workout app. Those who don't have an Apple TV can now watch fitness+ workouts on certain third-party TVs.
Other new features include a CallKitAPI that allows VOIP calls to be answered on Apple Watch, Apple Watch Mirroring for controlling the Apple Watch with an iPhone, and Quick Actions for doing more with a double pinch gesture.