WWDC 2017: watchOS 4 further refines Apple Watch for fitness
Monday, June 5, 2017 at 8:54PM 
By Gadjo Cardenas Sevilla
San Jose, CA - Apple introduced watchOS 4 today at the WWDC 2017 Keynote and said the updated wearable OS will deliver more intelligence and fitness functionality to users. A new Siri watchface brings proactive information when it is needed the most and is based on machine learning and Siri intelligence.
There will now be personalized activity coaching, a new music experience that syncs over playists and an enhanced workout app that ingegrates high intensity interval training. Another big feature is that Apple Watch will be able to synchronize with popular indoor gym equiptment, making tracking of stats and performance more accurate. This platform GymKit technology offers connected workouts with Apple Watch and cardio equipment. watchOS 4 will also introduce watchfaces based off Toy Story characters.