Nocturne Support

By default, Nocturne exports the full 5-minute HRV time series — the same granular format Apple Watch writes — and Apple Health computes its own averages from it. Eight Sleep's app shows a single nightly value from its proprietary algorithm.

If you want the numbers to match exactly, switch to Settings → HRV Export Method → Computed Average.

This usually means Eight Sleep's own Health sync is also enabled. Two options:

• Set Nocturne's export scope to HRV Only (Settings → Export Scope) and let Eight Sleep's native sync handle the rest. Eight Sleep's sync covers most metrics but skips HRV — Nocturne fills exactly that gap.
• Or disable Eight Sleep's Health sync and use All Sleep Data in Nocturne.

To clean up existing duplicates, use Settings → Delete All Nocturne Data from Health, then re-export with your preferred setup. This only removes entries Nocturne wrote — data from Eight Sleep's app or Apple Watch is untouched.

• Double-check your email and password in the official Eight Sleep app first.
• Nocturne signs you in directly with Eight Sleep — there is no separate Nocturne account.
• If your Eight Sleep account uses social sign-in (Apple/Google) without a password, set a password in the Eight Sleep app and use that.

Nocturne schedules background refreshes between 7:00 and 10:30 AM, but iOS ultimately decides when background tasks run based on battery, usage patterns, and Low Power Mode. To make it reliable:

• Keep Background App Refresh enabled (iOS Settings → General → Background App Refresh).
• Open the app occasionally — iOS prioritizes apps you actually use.
• Opening the app always syncs immediately, so your data is never more than one tap away.

Nocturne shows nights where Eight Sleep reported an HRV reading. Very short or incomplete sessions (e.g., the mattress couldn't get a stable reading) may not appear. Check whether the night shows HRV in the Eight Sleep app itself.

Anything that reads from Apple Health: Bevel, Athlytic, Training Today, HRV4Training (Health import), and more. Nocturne writes standard HealthKit types — HRV (SDNN), heart rate, resting heart rate, respiratory rate, and sleep stages.

Settings → Delete All Nocturne Data from Health removes everything Nocturne has written to Apple Health. Signing out removes your session token. Uninstalling the app removes everything else — Nocturne stores nothing off-device.