You can pair the Peloton bike with any heart rate monitor that uses ANT+. Plus, you can also use Bluetooth 4.0 to pair the Peloton bike to your headphones or speakers.
You can also pair the Peloton bike to your Fitbit account, allowing you to automatically post metrics from every ride you complete right to your Fitbit dashboard. Read more about how Peloton works with Fitbit here
In addition, if your smartwatch integrates with Strava, you can use our Strava integration to track your progress. Read more about how Peloton works with Strava here
The Fitbit and Apple Watch do not currently have ANT+ built in, so you cannot directly track your heart rate on the Peloton bike using these devices. However, you can wear your smartwatch/fitness tracker while you ride and have your metrics tracked separately.