Privacy Policy

Last updated: September 2026 · This is the Privacy Policy URL for the App Store listing.

The short version

Spline has no servers. Your health data is read from Apple Health, computed on your iPhone, and stored on your iPhone. There is no account, no sign-up, no cloud sync operated by us, and no analytics or advertising SDK in the app. We cannot see your data, because it never reaches us.

Data the app processes on your device

  • Apple Health (HealthKit): heart-rate variability, heart rate, resting heart rate, sleep, respiratory rate, wrist temperature, blood oxygen, blood pressure, glucose, ECG classifications, workouts, body composition and waist, VO₂max, mindful minutes, nutrition, caffeine and alcoholic drinks — each only after you grant permission for that specific data type. Spline writes back the food and drinks you log, waist measurements you enter, completed breathwork sessions and workouts you record in the app.
  • Lab results: PDFs and photos you import are parsed entirely on-device using Apple’s PDFKit and Vision frameworks. Nothing is uploaded.
  • What you type: journal entries, protocols, body measurements and training plans.
  • On-device language features: when you describe a meal, a workout or a routine, ask Spline a question, or scan a nutrition label, the text or image is processed on your iPhone — by Apple’s on-device model where Apple Intelligence is available, otherwise by built-in rules. It is not sent to us. If you use Siri or Shortcuts, Apple handles the voice request under your Siri settings; Spline answers from data already on your iPhone.
  • Widgets and Apple Watch: a small summary (today’s readiness, the call and tonight’s plan) is shared with Spline’s own widgets through an on-device container and sent directly to your paired Apple Watch. It never passes through a server of ours.

In line with Apple’s HealthKit requirements, health data is never used for advertising or marketing, and is never sold or shared with data brokers.

When data does leave your device

Only in these cases, and only because you chose them:

  • Food lookups: a barcode or search term is sent to Open Food Facts or USDA FoodData Central to retrieve nutrition information.
  • Polar: if you connect a Polar account, Spline requests your training and overnight data from Polar’s API using credentials stored in your device Keychain.
  • Backups you create: exporting produces a file. Where it goes — Files, AirDrop, your own iCloud Drive — is entirely your choice.
  • Share cards: if you share a day, session or month card, only the image on the card is shared, through the iOS share sheet, to wherever you choose.

Subscriptions

Spline Pro is sold as an in-app purchase through the Apple App Store. Apple processes the payment and is the seller of record; we never receive your payment details. We receive only aggregated, non-personal sales reports. Apple’s own privacy policy applies to that transaction.

Children

Spline is not directed at children under 16 and we do not knowingly process their data.

Your rights

Under the GDPR you have the right to access, rectify, erase, restrict, port and object to processing of your personal data. Because your health data lives only on your device, you exercise most of these directly: export it any time as JSON or CSV, or delete it by deleting the app. For anything else, contact us below. You may also complain to a data protection supervisory authority.

Website

This site sets no cookies, loads no external fonts, scripts or CDNs, and runs no analytics. The hosting provider records standard server logs (IP address, timestamp, requested file) for security, deleted within 30 days.

Contact

Maximilian Herold — health.spline.app@gmail.com
German-language version: Datenschutzerklärung · Provider details: Impressum