HeartTXHEARTTX HELP
Set up. Pair. Ride.
A direct connection from your wrist to your workout.
Download HeartTX for free on the App Store and install it on your Apple Watch.
Connect to Zwift on Apple TV
- Wear your Apple Watch securely and turn on Bluetooth. Keep it near Apple TV.
- Open HeartTX. Tap Start for a session without a time limit, or Timer to choose a duration.
- Allow access to heart rate, workouts and Bluetooth when prompted. Workout access lets HeartTX measure continuously; the temporary workout is discarded at the end.
- In Zwift, open device pairing, choose Heart Rate and select HeartTX. Wait for a fresh pulse reading.
- Tap Stop on your watch when finished. A timed session stops automatically.
The heart rate travels directly from the watch to the Bluetooth receiver. An iPhone does not relay it.
Set an automatic stop
Tap Timer, choose 1–240 minutes using the Digital Crown or the picker, then tap Start. The last selected duration is remembered on the watch; the initial default is 60 minutes.
The countdown starts after measurement begins, so time spent granting permissions does not use up your session. A short haptic signals the automatic stop. You can stop earlier at any time. The next ordinary Start has no countdown.
Troubleshooting
HeartTX does not appear in the pairing list
Start a HeartTX session before searching. Keep the app visible for initial pairing and bring the watch closer to Apple TV. Confirm Bluetooth access for HeartTX in Settings. Disconnect unused Bluetooth accessories or other apps that are connected to HeartTX, then stop and restart the session and scan again.
The watch shows a dash instead of a pulse
A dash means there is no fresh reading. Check the watch fit and heart rate permission, then wait for a new measurement. HeartTX hides readings older than 10 seconds. The system does not tell the app whether heart rate read access was denied, so check Health permissions if the dash remains.
The session stops unexpectedly
Another workout app can end the current session. Avoid starting a separate workout on the watch while HeartTX is running. Also check whether you selected a timer. If a Bluetooth error appears, stop, verify Bluetooth is enabled and try again.
Can I return to the watch face?
Yes. HeartTX uses a workout session to continue measurement. Background reception and reconnection have been tested on the developer’s test watch. Keep the watch on your wrist; long sessions and other watch models still need further testing.
Does HeartTX save a workout?
HeartTX discards its temporary workout at the end. Apple Watch may still record health samples or contribute to Activity rings. Your receiving fitness app may save its own workout.
Which devices are supported?
The current build requires watchOS 26 or later and has been tested on Apple Watch Ultra with watchOS 27.0.1. The confirmed receiver is Zwift on Apple TV. Other combinations are not yet verified. HeartTX is available free on the App Store. Layouts have also been checked in the watchOS simulator on 40–46 mm SE and Series sizes; Bluetooth and heart rate on those physical models still need testing.
Contact the developer
mat.kramarik@gmail.comHeartTX is developed by Matus Kramarik, Czechia. In your message, include your watch model, watchOS version, receiving device and the error text or steps that caused the problem. Please do not send health history, passwords or other sensitive information.
For privacy or deletion requests, use the same address. HeartTX has no user accounts to delete.