Garmin heart-rate broadcast during a workout: device-agnostic HRM naming + ANT+ reception (narrows #1326) #1359

Reporter: shredness_10860 (Discord, #feature-requests, thread 1564577349666607135)
Type: Enhancement / feature request
Repo: 9thlevelsoftware/project-phoenix-mp (mobile)
Requested: app listens for a Garmin device heart-rate broadcast during a workout

Summary

The user wants the Phoenix mobile app to listen for a Garmin device heart-rate broadcast during a workout and show and record live heart rate. Garmin devices broadcast heart rate over two distinct radio paths — standard Bluetooth Low Energy (BLE) Heart Rate Service 0x180D, and ANT+ — so Garmin HR support is two separable concerns.

Relationship to in-flight PR #1326 (read before scoping work)

Open PR #1326 — feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics (author StuGotz, branch feature/polar-h10-telemetry, currently mergeable: CONFLICTING) — already implements a standard Bluetooth-SIG heart-rate path, not a Polar-proprietary one. Because Garmin Broadcast Heart Rate over BLE advertises the same standard 0x180D service, #1326 largely covers the BLE half of this request already:

• Discover device: isPolarH10Advertisement() matches name prefix Polar H10 OR any advertisement carrying Heart Rate Service 0x180D -> covers Garmin (BLE)
• Parse HR stream: parsePolarHrMeasurement() decodes standard 0x2A37 -> covers Garmin (BLE)
• Contact gating: contact-status flags map 0/1 to contact-OK, so telemetry is not dropped when a device reports Sensor Contact NOT supported -> covers Garmin
• Battery gate: isBatteryCritical() is null-safe when 0x2A19 is absent -> covers Garmin
• Polar proprietary PMD/ECG/ACC: best-effort in try/catch, does not block connect -> degrades gracefully on non-Polar
• Live / session / post-workout HR: PolarH10WorkoutStrip, MetricSample.heartRateBpm, WorkoutSession HR plus HRR60/HRR300 -> covers Garmin (BLE)

This issue is NOT a request to build BLE HR from scratch. It is scoped to the genuine gaps below.

Requested work (the gap)

1. ANT+ heart-rate reception (the real missing capability). Garmin common gym-broadcast mode is ANT+, a separate radio and protocol from BLE. There are currently zero antplus / ant+ / garmin references in the feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326 diff. Adding ANT+ HR reception is the primary new work. Platform limit: ANT+ is Android-only (iOS exposes no public ANT+ API); on iOS Garmin HR must come over BLE 0x180D (already handled by feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326). State this limit so iOS users are not promised ANT+.
2. Device-agnostic naming and UX (BLE and ANT+). The feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326 HR layer is Polar-hardcoded and will mislabel Garmin hardware: a nameless advertisement defaults to the label Polar H10; settings keys are polar_h10_*; UI components and logs read PolarH10SettingsCard, PolarH10WorkoutStrip, and a Connected to Polar H10 log line. Rename to device-agnostic identifiers, keys, and logs so a Garmin (or any 0x180D / ANT+ HR sensor) is labeled correctly and its settings do not collide with Polar-specific ones.
3. HRV / RMSSD completeness (nice-to-have). RR intervals are parsed from standard 0x2A37, so HRV/RMSSD works only if the specific Garmin unit emits RR intervals over BLE. Torso biomechanics and ECG (FB005C82) are Polar-proprietary and irrelevant to Garmin; do not attempt to map them.

Expected behavior

The app discovers and pairs a Garmin watch or chest strap broadcasting heart rate (BLE 0x180D on iOS and Android; ANT+ on Android), shows live HR during a workout, and records avg/max/min HR (and HRR where available) to the session, with the hardware correctly labeled as the Garmin device rather than Polar H10.

Actual behavior / current state

• BLE standard-HR discovery and parsing exists in open PR feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326 but is not yet merged (CONFLICTING) and its naming is Polar-specific.
• ANT+ HR reception does not exist anywhere in the codebase.

Impact / notes

• High value for Garmin users (running, cycling, and gym HR broadcast is a common setup).
• Nothing here ships until PR feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326 merge conflicts are resolved and it lands; this feature builds on that HRM layer.

Acceptance notes / verification caveat

• The feat(polar): add Polar H10 concurrent BLE telemetry, 3D torso biomechanics, and HRR analytics #1326 coverage above is derived from reading the PR diff, not from a running build. A real Garmin pairing is NOT verified. The Phantom harness cannot verify physical Bluetooth/RF/firmware — it covers app UI/state/persistence and deterministic simulator behavior. The real acceptance gate is a physical-device pairing test (Garmin watch or chest strap to app, live HR during a workout), on Android for ANT+ and on iOS for BLE.

Attachments

No attachments recorded on the Discord report.

Original Discord report (verbatim)

<@1502654170031849644>  Feature request: "listen" for Garmin heart rate broadcasting during a workout

Discord-Message-ID: 1564577349666607135