Polar H10 on iPhone with Beatcast

Beatcast verified

Updated 2 November 2026

Short answer

Beatcast is a third-party app for the Polar H10 on iPhone. It shows the strap's live heart rate in big numbers, in the Dynamic Island and on the Lock Screen, and the number stays there while you use other apps. The readout takes the colour of your zone. Leave your target zone and Beatcast tells you by sound, voice, haptic or notification, even with the phone locked in a pocket. Sessions are saved with time in zone. The live number needs no Polar app.

The H10 is Beatcast verified: I tested it myself. It sends the standard Bluetooth heart rate service. Put it on with damp electrodes, open Beatcast and pick it from the sensor list.

Last checked: 2 November 2026.

What works, and what to expect

Works: live heart rate in any app that speaks the standard service.
Works, with a setting to check: two apps at once. Polar's current manual lists two simultaneous Bluetooth connections and shows the "2 Bluetooth devices" setting on by default in Flow. An older Polar support article says the H10 usually serves one at a time. Check the setting in Flow.
Works: the Polar H9. It uses the same service.
Won't work: a strap that is held by something else when you ask for it. More on that below.

Wake it up

Moisten the two electrode areas on the strap, put it on, and give it a few seconds. Polar's manual notes that sweat and moisture can keep the electrodes wet and the sensor active, so rinse the strap after use. As far as I know the H10 wakes when damp electrodes touch skin. Beatcast's own hint for a missing sensor says most only show up once they can feel a heartbeat.

Wear it wherever it reads for you. Beatcast is happy with any position.

Find it in the app

You pick the strap inside the app, from its list of sensors. Beatcast connects without bonding and has no allow-list, so there is nothing to set up in iOS Settings. Allow Bluetooth for the app when it asks, and the strap appears.

If it never shows, the usual cause is that something else already has it. A watch, a bike computer, another app or Polar's own app can hold the connection. Close those and look again. The checklist for a strap that will not connect goes through the rest in order.

Two devices at once

Polar's support article gives the steps for turning the second connection on. In the Polar Beat app, open Settings, then HR sensor, pair the H10, and turn on "2 receiving BLE devices". In Polar Flow, start a training, pair the sensor from the settings cogwheel, and enable "2 Bluetooth devices". For Beat the H10 needs firmware 2.1.9 or newer. The page lists no firmware requirement for Flow.

The full model-by-model list is on the two devices page.

The H9

The H9 is covered here because the questions are the same. It uses the same standard profile. If you try it with Beatcast, say how it went in r/beatcast.

What Beatcast does with the number

Start a session and the number moves into the Dynamic Island and onto the Lock Screen, and into StandBy when the phone is charging on its side. With the phone propped up, the readout fills the screen, which stays awake for the whole session.

The zones work out of the box. You can have two, three or five, based on a percentage of maximum heart rate, on Karvonen or on a percentage of threshold heart rate, or set your own. Sessions are kept with time in zone and exported as CSV or TCX, and finished ones can go to Apple Health if you switch that on.

Straps are the main reason Beatcast exists. Beatcast on the App Store. Fourteen days free, then one purchase. No subscription, no account.

Questions

Do I need Polar's app?

No, for live heart rate. Polar Beat and Polar Flow are where you update the strap's firmware and change its settings.

Why is my H10 not showing up?

Almost always it is asleep or connected elsewhere. See the not connecting checklist.

Can it feed Beatcast and a watch together?

Polar's manual lists two simultaneous Bluetooth connections. Check that the "2 Bluetooth devices" setting is on in Flow.

Which apps work with it?

Any app that reads the standard Bluetooth heart rate service. There is a short guide to connecting a Bluetooth monitor.

Good to know

Beatcast is not a medical device. It is built for training and general wellbeing, and it cannot detect, diagnose, treat or monitor any condition. If something about your heart worries you, talk to a doctor rather than to an app.

The Bluetooth word mark is a registered trademark of Bluetooth SIG, Inc. Apple, iPhone, Apple Health, Dynamic Island, Lock Screen and StandBy are trademarks of Apple Inc. Polar is a trademark of Polar Electro Oy, and other names belong to their owners. They are used only to say which sensors Beatcast can read. Beatcast is an independent product and is not affiliated with, endorsed by or certified by any of them.

Got your strap working? Report it in r/beatcast and it goes on the list.