The Apple Watch does not broadcast HR over standard Bluetooth or ANT+ channels, so we are not able to connect to it. In order to do so, we would need to build a specific Watch OS app and that's not something we have on our current roadmap. We highly recommend a chest heart rate strap as it will be more responsive and accurate. For details about compatible sensors, please see: Connect your Sensors.
The app does not share data with Apple Health. However, you may share your data with other Apple Health-enabled apps such as Strava. For more about setting up sharing, please see the following link: