HealthKit Integration in ChantFlow: Heart Rate, HRV, and Mindful Minutes

Chanting helps you feel calm. Now ChantFlow helps you see it, too. We’ve added gentle HealthKit integration so your Apple Watch can reflect what your body experiences during practice — without turning your wrist into a spreadsheet. See the app here: ChantFlow and on the App Store: ChantFlow — Daily Om Practice.

What’s new

• Heart rate insights: See your BPM during and after sessions — today and across the week.
• Mindful Minutes in Health: Your sessions are logged to Apple Health as Mindfulness.
• HRV (experimental): Heart Rate Variability appears after a session when conditions are right.
• Simple Health Insights screen: Big, readable numbers. Built for quick glances.

Why this matters

• Feel it, then see it: A calm heart rate trend is a gentle nudge to keep going.
• HRV as a signal, not a score: It can reflect resilience. We show it when it’s reliable.

How it works

• When you chant, the app quietly starts a health session.
• We read heart rate during the session, summarize after.
• HRV usually becomes available after ending the session and needs 3–5+ minutes of stillness and good sensor contact.
• Your Mindful Minutes are saved to Apple Health (with your permission).

Tiny code you can use

Request Health permissions (read HR/HRV, write Mindfulness + Workout)

import HealthKit

let healthStore = HKHealthStore()

func requestHealthPermissions(completion: @escaping (Bool) -> Void) {
    let toShare: Set = [
        HKObjectType.categoryType(forIdentifier: .mindfulSession)!,
        HKObjectType.workoutType()
    ]
    let toRead: Set = [
        HKObjectType.quantityType(forIdentifier: .heartRate)!,
        HKObjectType.quantityType(forIdentifier: .heartRateVariabilitySDNN)!
    ]
    healthStore.requestAuthorization(toShare: toShare, read: toRead) { ok, _ in
        completion(ok)
    }
}

Log a Mindfulness session to Apple Health

import HealthKit

func saveMindfulMinutes(start: Date, end: Date, completion: @escaping (Bool) -> Void) {
    let mindful = HKObjectType.categoryType(forIdentifier: .mindfulSession)!
    let sample = HKCategorySample(type: mindful, value: 0, start: start, end: end)
    HKHealthStore().save(sample) { ok, _ in
        completion(ok)
    }
}

(Optional) Start a lightweight workout for live heart rate on watchOS

import HealthKit

final class LiveHRSession: NSObject, HKWorkoutSessionDelegate {
    private let store = HKHealthStore()
    private var session: HKWorkoutSession?
    private var builder: HKLiveWorkoutBuilder?

    func start() throws {
        let cfg = HKWorkoutConfiguration()
        cfg.activityType = .mindAndBody
        cfg.locationType = .unknown
        let session = try HKWorkoutSession(healthStore: store, configuration: cfg)
        let builder = session.associatedWorkoutBuilder()
        builder.dataSource = HKLiveWorkoutDataSource(healthStore: store, workoutConfiguration: cfg)
        self.session = session
        self.builder = builder
        session.delegate = self
        session.startActivity(with: Date())
        builder.beginCollection(withStart: Date()) { _, _ in }
    }

    func stop(completion: @escaping () -> Void) {
        builder?.endCollection(withEnd: Date()) { _, _ in
            self.session?.end()
            self.builder?.finishWorkout { _, _ in completion() }
        }
    }

    func workoutSession(_ workoutSession: HKWorkoutSession, didChangeTo toState: HKWorkoutSessionState, from fromState: HKWorkoutSessionState, date: Date) {}
    func workoutSession(_ workoutSession: HKWorkoutSession, didFailWithError error: Error) {}
}

Privacy, always

• You’re in control: Permissions are requested clearly during onboarding (new users) or at launch (existing users).
• Minimal data: We read only what’s needed. We don’t write HRV to Health. We don’t sell or share your data.
• On‑device first: Data is handled with care for speed and privacy.

Accessibility and design

• Big text, clean layout, VoiceOver‑friendly.
• Built for short sessions and quick checks, not deep dives.

HRV: set the right expectation

• HRV is experimental. It often appears after you end a session, and only with steady, still wear for several minutes. Heart rate will show up almost every time — HRV will show up some of the time. That’s normal.

Tips for better readings

• Wear the watch snugly, above the wrist bone.
• Keep your wrist still during the session.
• Aim for at least 5 minutes if you’re hoping to see HRV.

What’s next

• Gentle trends over weeks and months.
• Clear, friendly insights like “Your average heart rate during chanting dropped this week.”
• Continued focus on privacy and accessibility.

Start a session, breathe, and take a peek at your Health Insights afterward. Calm feels good — and now you can see it, too.