The Apple Watch can be used to join a Group Fitness session as a heart rate monitors.
These are the steps to add the Apple Watch to your Group Fitness sessions
1) Your clients need to install the Selfloops Spark app from the App store and grant the Health options. The Selfloops Spark iPhone app includes the Apple Watch app
2) Assign an Apple Watch sensor to your client in the Equipments section in the website
3) Synchronize your clients on your device (iPad, Apple TV, Android)
4) Press START on the app
5)Your clients can start the Group Fitness workout on their Apple Watch