HeartRate Broadcaster

Your Apple Watch already measures your heart rate. This puts that number on your bike computer, your trainer app, or anything else that pairs a Bluetooth chest strap.

HeartRate Broadcaster turns your iPhone into a standard Bluetooth heart rate monitor, fed by the sensors you already wear.

Your Apple Watch and AirPods Pro 3 measure your heart rate continuously, but nothing else can read them. Training apps and bike computers expect a Bluetooth chest strap. HeartRate Broadcaster bridges the two: it reads live heart rate from your watch and AirPods, reconciles them into a single reading, and rebroadcasts it as a standard Bluetooth LE Heart Rate Service. Your training app sees an ordinary strap.

TWO SENSORS, ONE NUMBER When the watch and AirPods both report, the app averages readings that agree and rejects the outlier when they disagree, preferring whichever is closer to the trend it has already seen. Head units only ever see one sensor. The Sensor Agreement row shows which sensors are live, how far apart they are, and which number went out — so you never have to take the app's word for it.

GLANCEABLE WHILE YOU RIDE A Live Activity puts the current BPM, its source, and whether a head unit is actually subscribed on the Lock Screen and in the Dynamic Island. Picture in Picture keeps the number floating over your training app. On the watch, a one-second press locks the touch screen against a jersey sleeve or a grab at the bar tape; another press releases it.

DIAGNOSTICS THAT TELL THE TRUTH Connected devices by identifier, frames sent per subscriber, live frame rate, the exact bytes of the last frame, and how long ago it went out. When something is not working, you can see which half of the link is at fault. A permissions screen shows every permission the app needs, what it is currently set to, and a direct link to change it.

WHAT IT CANNOT DO Apple provides no API for a third-party app to read a Bluetooth chest strap or another phone's sensors, so this app cannot import one. It broadcasts over Bluetooth LE only — ANT+ is a separate radio that iPhones do not have.

Works with MyWhoosh, Zwift, TrainerRoad, Wahoo, and Bluetooth-capable Garmin Edge units. Requires iOS 26 and, for the watch app, watchOS 11.