Polar H12 appears inside Polar Flow app code

Our teardown of the latest Polar Flow app has revealed references to what appears to be an unreleased Polar H12 heart rate sensor.

The name shows up in several parts of the app code. This includes a dedicated device definition and sensor registration support, making the finding considerably more interesting than a single leftover string.

Polar H12 is hiding inside Flow

We took a closer look at Polar Flow 7.36.2 to see whether the latest release contained any hints about upcoming hardware. Polar officially describes this version as a relatively minor update that fixes connectivity issues, but there is more sitting under the surface.

One of the more interesting entries is a device specification class named PolarSensorGardener.

Inside it are the names Polar H12 and H12.

That alone would be worth noting, but there is considerably more supporting evidence. The app identifies the device as a heart-rate sensor, allows it to be registered as a sensor and includes it among devices considered published by Flow’s internal device-handling logic.

H12 also appears in Polar Flow’s sensor registration code alongside familiar products including H6, H7, H9, H10, Polar Pro, OH1 and Sense. Another part of the app includes H12 among the sensors that support Polar’s Fitness Test.

The Gardener class is particularly interesting because parts of it still look unfinished. It contains placeholder product text including Polar xxx Heart Rate Sensor and Polar xxx, while one of the support links still points to information for the existing H10.

That combination suggests Polar has created a working device profile before completing all the consumer-facing information.

H12 would make sense as an H10 successor

Polar currently lists three main heart-rate sensors on its official sensor page: the H9, H10 and Verity Sense. There is no H12.

The H10 has also been around for a long time. We reviewed the device back in 2017, so a new higher-end chest sensor would hardly be unexpected after nearly a decade.

What H12 might actually add is impossible to tell from the current code. There are no obvious specifications covering battery life, connectivity or new sensing capabilities.

One other question is whether this has anything to do with the recently filed Polar Pulse trademark. The company made its filing in Europe on July 9, followed by a US filing on July 15. The paperwork covers things such as wearable devices, biometric measurements, software and exercise coaching, so it is broad enough to cover quite a few possibilities.

Naturally, that makes you wonder whether Polar Pulse and H12 are connected. We checked the Flow code for the name, but found nothing tying Polar Pulse to H12 or the Gardener codename. So for now, these look like two separate leads rather than pieces of the same puzzle.

H12 is still the more interesting one. Polar Flow already has a dedicated device profile and explicit sensor support for it, which is much more concrete than a trademark filing. We still do not know when it might launch, what it adds over the H10, or whether H12 will even be the final retail name.

This article originally appeared on Gadgets & Wearables, the first media outlet to report the story.