NightRing
Sleep rhythm rings & insights
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
"When did I fall asleep last night?" — NightDial answers the moment you open it.
It reads the sleep data your Apple Watch or iPhone already saves to Health, and draws each night as an arc on a 24-hour dial. Zero input required. Just sleep like you always do.
■ Sleep Rings
Sleep that crosses midnight stays whole on a circle. Bedtime to wake-up, one arc, one glance.
■ A calendar of rings
One ring per day, a month at a time. Aligned arcs mean a steady rhythm — the messy nights stand out instantly.
■ Sleep Score
Duration, rhythm, continuity, and timing — scored every morning, with the full breakdown visible. You'll know exactly what to fix.
■ Today's Note
One piece of advice a day, picked for your recent sleep pattern from thousands of pre-written insights.
■ Night Vitals (Apple Watch)
Heart rate, respiratory rate, blood oxygen and more, shown alongside each night.
■ Social Jet Lag
See exactly how far your weekends drift from your weekdays — in minutes. Now you know why Mondays hurt.
■ Privacy
Your sleep data is processed entirely on your device and never leaves it.
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NightDial Plus (subscription)
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The free version fully covers your last 14 days, plus today's score and advice. With Plus you get:
- Your entire history, as far back as it goes
- Trend charts: bedtime, wake time, score, nightly heart rate
- Detailed weekday vs. weekend analysis
- No ads
Pricing: $0.99/month, $6.99/year (with 7-day free trial), or $16.99 lifetime.
Subscriptions renew automatically unless cancelled at least 24 hours before the end of the period. Manage or cancel anytime in your App Store account settings.
Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://kakovail.info/privacy/
* Requires sleep data in Apple Health (from Apple Watch, or iPhone with a sleep schedule).
* NightDial shows rhythm insights only and does not provide medical evaluation or advice.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
A complete visual redesign—quieter and easier on the eyes for an app you open at night.
You can now switch the language and theme (Light/Dark) in Settings.
The developer, Hiroyuki Kako, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Usage Data
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Hiroyuki Kako
- Size
- 5.7 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English and Japanese
- Age Rating
4+
- 4+
- Contains
Advertising
- In-App Purchases
Yes
- Plus Yearly $11.99
- Plus Monthly $1.49
- Coffee $2.99
- Dinner $29.99
- Good Burger $9.99
- Plus Lifetime $24.99
- Copyright
- © 2026 Kako no Nikomi