Privacy Policy

Effective date: 18 September 2026 · Last updated: 27 September 2026

1. Who we are

Spira (“spira”, “we”, “us”) is an audio-guided physiological training app for VO₂max interval training and breathwork. Some features are free; others are available through an optional paid subscription, spira Premium.

The data controller responsible for your information is:

If you are in the EU/EEA and have questions about your data, contact us at the address above.

2. Our approach to your data

Spira is built to be local-first. Spira does not require an account. You do not create a username or password, and we do not ask for your name or email to use the app. Your training history, profile details, and session data are stored locally on your device, not on our servers.

We collect the minimum needed to (a) make the app work, including subscriptions if you choose to buy one, (b) keep it stable, and (c) understand—anonymously, and only if you agree—how the app is used so we can improve it.

3. What data is processed, and where

a) Data stored only on your device (we never receive it)

  • Profile: age, biological sex at birth, height, weight, resting heart rate, maximum heart rate. Used to personalise training zones and guidance.
  • Session history: protocols completed, duration, modality, timestamps, and heart-rate metrics from your sessions.
  • Programme progress and settings (cue styles and other preferences), including the name of the last heart-rate monitor you connected.
  • Your analytics choice (see section 3(d)).
  • A cached record of your subscription status, so spira Premium keeps working when you are offline.

This information stays on your device (local storage) and is removed if you delete the app.

b) Apple Health (HealthKit) — only with your permission

If you grant permission, Spira can:

  • Read heart rate — for example from Apple Watch, Oura, Withings, or other Health-connected devices — to show your metrics during and after a session.
  • Write your VO₂max sessions to Apple Health as workouts, and your breathwork sessions as Mindful Minutes.

Apple Health data is processed on your device for these features. We do not send your Apple Health records or values to our servers or to any third party, and we never use them for advertising. You can revoke Health access at any time in iOS Settings → Privacy & Security → Health. Spira still works without it.

c) Bluetooth heart-rate monitors — only with your permission

If you connect a supported Bluetooth heart-rate monitor, Spira reads live heart-rate data during your session to display your zones and metrics. This data is processed on your device. We do not transmit it to our servers.

d) Anonymous usage analytics (PostHog) — optional, off unless you choose it

To understand how Spira is used and where it can be improved, the app can collect anonymous usage analytics using PostHog, hosted in the European Union. This analytics runs inside the app only — the withspira.com website does not use analytics or tracking scripts.

Analytics are opt-in.

  • When you first set up spira, you choose whether to share anonymous analytics. Nothing is sent until you choose to share.
  • If you used spira before this choice was introduced, analytics stay off until you turn them on.
  • You can change your choice at any time in the app: Settings → Share anonymous analytics. Turning it off takes effect immediately.
  • Declining analytics does not limit any spira feature.

If you choose to share, the app sends events about how the app is used, for example:

  • opening the app, starting and completing setup, and whether you imported your profile from Apple Health during setup;
  • sessions started, completed, or ended early — including the protocol or programme identifier, the equipment you chose (for example treadmill or bike), how much of the session was completed, and the phase at which a session was ended;
  • session timing details, such as how long a breathwork introduction played;
  • whether a heart-rate source was connected and which kind (Bluetooth monitor or Apple Health), whether live heart rate was available during a session, when heart-rate data became available for a session, and whether a monitor disconnected or reconnected;
  • programme progress (programme identifier and session number), opening the Progress screen, and creating a share card;
  • a random identifier for each session, so events from the same session can be matched;
  • technical context such as device type and model, operating-system version, and screen size.

This data is tied to a random, app-generated identifier — not to your name, email, or any account (there is no account). We have disabled IP-based location lookup in our analytics configuration.

We do not send heart-rate values, heart-rate zones, VO₂max values, Apple Health records, age, sex, height, or weight to analytics. We do not use analytics to track you across other apps or websites, and we do not sell it.

e) Subscriptions and purchases (Apple and RevenueCat)

spira Premium is sold as an auto-renewing subscription through the Apple App Store.

  • Apple processes your payment. We do not receive your payment card details or billing address. Your subscription is managed through your Apple Account.
  • RevenueCat (RevenueCat, Inc.) is the service we use to check and manage subscription access. Each time you open spira, the app asks RevenueCat whether you have an active subscription — including if you have never bought one — so that premium content unlocks (or stays locked) correctly.

The app explicitly provides RevenueCat with:

  • an anonymous app user identifier generated for your installation of spira — not your name, email, or Apple Account credentials;
  • the App Store purchase and subscription information needed to manage your access, such as the product purchased, purchase and renewal dates, subscription status, and the store’s country and currency;
  • basic technical information such as device type, operating-system version, and app version.

In addition, RevenueCat may process technical connection information, such as an IP address, as part of providing its service — in the same way most internet services do when your device connects to them. We do not separately collect or forward your IP address to RevenueCat, and we do not use it ourselves.

If you use Restore Purchases, the app asks Apple for your App Store purchase history and shares it with RevenueCat so your existing subscription can be restored.

Spira does not intentionally provide RevenueCat with health, heart-rate, workout, or analytics data.

f) Crash and error reporting (Sentry)

To keep the app stable, we use Sentry to collect crash and error diagnostics from the app (not from this website). Data is stored in the European Union. Reports contain technical information: error details, device and OS version, app version, and the state of the app at the time of the problem. A sample of performance measurements (for example how long certain operations take) is also collected. We configure Sentry not to collect personal information, and we remove user identity fields from error reports; reports are not linked to your name or email.

If a lookup of heart-rate data in Apple Health fails or returns nothing, the report can include technical details of that lookup — for example how many samples it returned — but never the heart-rate values themselves or other Apple Health records.

Crash and error reporting is separate from the analytics choice in section 3(d) and runs whether or not you share analytics, because it is needed to find and fix problems.

g) Website waitlist (Formspree)

If you join the waitlist on withspira.com, the email address you submit is collected and processed on our behalf by Formspree, acting as our processor. We use it only to contact you about spira’s availability and launch. We do not use it for any other purpose, and we do not share it further. You can request deletion of your email at any time by contacting hello@withspira.com.

For users in the EU/EEA, we rely on:

  • Consent — for Apple Health access, Bluetooth access, usage analytics, and the website waitlist. You can withdraw consent at any time; for analytics, use Settings → Share anonymous analytics in the app.
  • Performance of a contract — to provide the training features you request and, if you buy spira Premium, to provide and verify your subscription (including through Apple and RevenueCat).
  • Legitimate interests — for crash/error diagnostics needed to keep the app secure and functioning, balanced against your rights.

5. Who we share data with

We do not sell your data. We share data only with the service providers that operate the app’s infrastructure, strictly to provide the service:

  • PostHog (EU) — anonymous product analytics, only if you choose to share them.
  • Sentry (EU) — crash and error diagnostics.
  • RevenueCat — subscription status and purchase management.
  • Apple — app distribution, payment processing for subscriptions, and, where you use them, Apple Health and other platform services.
  • Formspree — waitlist email collection on our website.

These providers act as our processors under contract, except Apple, which processes payments and App Store data under its own terms and privacy policy. Apple Health and on-device training data are not shared with any of them.

6. International transfers

We host analytics and diagnostics in the European Union. RevenueCat is based in the United States. RevenueCat’s data processing agreement provides for the European Commission’s Standard Contractual Clauses for restricted transfers, where applicable. Where any other provider processes data outside the EU/EEA, we rely on comparable appropriate safeguards.

7. Data retention

  • On-device data (profile, sessions, programme progress, settings, analytics choice, cached subscription status): kept until you delete it in the app or uninstall the app.
  • Analytics and crash data: retained only as long as needed for the purposes above, in line with our providers’ standard retention periods, then deleted or anonymised.
  • Subscription records held by RevenueCat: kept as long as needed to manage your subscription access and to meet legal and accounting obligations. Apple keeps its own purchase records under its own policies.
  • Waitlist emails: kept until we have notified you of launch, or until you request deletion, whichever comes first.

8. Your rights

Subject to applicable law (including the GDPR), you have the right to access, correct, delete, restrict, or object to the processing of your personal data, and to data portability. Because most of your data lives only on your device, you can exercise much of this directly: edit your profile, delete sessions, turn analytics off in Settings, or uninstall the app to remove local data. For analytics, crash, subscription, or waitlist data, contact hello@withspira.com and we will action your request. You may also lodge a complaint with your local data protection authority (in France, the CNIL).

9. Children

Spira is not directed to children and is intended for users aged 16 and older. We do not knowingly collect data from anyone under 16. If you believe a younger child has used the app, contact us.

10. Security

We use reputable providers and reasonable technical measures to protect data. No method of transmission or storage is completely secure, but keeping your training data on your device by default reduces exposure.

11. Not medical advice

Spira provides training guidance only and is not medical advice. It does not diagnose, treat, or monitor any medical condition. Consult a qualified professional before beginning any intense exercise programme.

12. Changes to this policy

We may update this policy as the app evolves. We will post the updated version here and change the “Last updated” date. Material changes will be communicated in-app where appropriate.

13. Contact

Questions about privacy: hello@withspira.com