Privacy Policy

Last updated: November 3, 2026

The short version. Tervy reads your Apple Health data on your iPhone and analyses it there. Your health data, your changes, answers, day ratings, notes and tags stay on your iPhone and Apple Watch. There is no account and no Tervy server that stores them. The app sends anonymous usage events (for example, which screen was opened) to help us understand how it is used. Those events never contain health values, ratings, notes, tags or the names of your changes. Purchases are handled by Apple and RevenueCat. We never sell your data, and we never use health data for advertising.

This Privacy Policy explains what information the Tervy app ("Tervy", "the app") and the website tervy.app ("the website") process, why, and what choices you have. It applies to the iPhone app, the Apple Watch app, its widgets and Shortcuts, and the website.

Who is responsible

Tervy is developed by Jiří Urbášek, an independent developer, Chářovská 60, 794 01 Krnov, Czech Republic ("we", "us"). We are the controller of the personal data described in this policy. You can reach us at support@tervy.app or at the postal address above.

1. Data that stays on your device

The following data is created, stored and processed only on your iPhone and, where you use it, your Apple Watch and the widgets on your device. We have no access to it.

• Your changes and records: the changes you start (name, icon, colour, target, schedule, start and end days), your daily marks (Done, Not today, Skip), logged amounts, check-ins, day ratings, notes and tags.
• Apple Health data: with your permission, Tervy reads the following from Apple Health: resting heart rate, heart rate, walking heart rate average, heart rate variability, sleep analysis (including sleep stages), steps, exercise time, workouts, time in daylight, VO2 max, respiratory rate, blood oxygen, wrist temperature, body mass, mindful sessions and alcoholic beverages. You choose which of these to allow in the Apple Health permission screen, and you can change it at any time in the Health app or in Settings → Privacy & Security → Health.
• Data Tervy writes to Apple Health: if you allow it, drinks you log in Tervy are saved to Apple Health as alcoholic beverages. Nothing else is written.
• Calculations: your usual ranges, baselines, comparisons and every other result Tervy shows are computed on your device.
• Diagnostics log: a technical log kept on your device. It leaves the device only if you choose to share it, for example by sending it to us with a support request.

This on-device data is included in your device backups (iCloud Backup or a computer backup) according to your own device settings, which Apple handles under its privacy policy. Tervy does not use iCloud sync or any server of its own to store it.

How we treat Apple Health data

• Health data is used only to show you information inside Tervy.
• It is never sent to us, to our analytics provider or to any other third party.
• It is never used for advertising, marketing or data mining, and it is never sold.
• It is never used to decide anything about you automatically, and never shared with insurers, employers or data brokers.

2. Data that leaves your device

Anonymous usage analytics (PostHog)

To understand how the app is used and which parts need work, Tervy sends usage events to PostHog, an analytics service. We use PostHog's EU cloud, which stores data in the European Union.

• What is sent: events such as "onboarding screen viewed", "tab viewed", "change started" or "change marked", with properties limited to fixed values (for example the screen name, the kind of change such as "earlier bedtime", whether a mark was set or cleared, counts, time spent on an onboarding screen, the app version, device model and operating system version, your App Store country, and whether you use the free version or Premium). Your answers to the onboarding questions (for example what you'd like to work on) are sent as fixed answer codes.
• What is never sent: health values or any Apple Health data, results of comparisons, day ratings, notes, tags, the names you give your changes, any free text, and whether you marked a day Done, Not today or Skip.
• Identifier: events are linked to a random identifier created by the app. It isn't your name, email, Apple ID or advertising identifier (Tervy doesn't use the advertising identifier). Choosing "Erase everything" in Settings resets this identifier.
• Onboarding screen recordings: on some onboarding screens, the app records what is shown on screen and your taps (session replay), so we can see where the onboarding is confusing. Recording is off everywhere else in the app, stops before onboarding ends and whenever the app leaves the screen, and screens that show your Apple Health data are never recorded. Recordings are linked to the same random identifier as the events, never to your name or Apple ID.
• Network data: like any internet service, PostHog receives your IP address when the app sends events. We don't use it to identify you.

Legal basis: our legitimate interest in understanding and improving the app (Art. 6(1)(f) GDPR), using data that cannot reasonably identify you and excludes all health data.

Purchases (Apple and RevenueCat)

Premium subscriptions and the lifetime purchase are processed by Apple through the App Store. We never see your payment details. To check whether you have Premium, Tervy uses RevenueCat, a subscription management service. RevenueCat receives an anonymous app user ID, your App Store purchase receipts and transaction history, your App Store country, device and app version information, and the random analytics identifier described above, so purchase events can be counted in our analytics. If you allow it under Apple's rules, RevenueCat may also receive an Apple Search Ads attribution token (see below). Legal basis: performance of the contract with you (Art. 6(1)(b) GDPR).

Apple Search Ads attribution

Tervy uses Apple's AdServices framework to learn whether the app was installed after you tapped an Apple Search Ads ad. Apple returns campaign identifiers (such as the campaign and keyword ID), not information about you, and does not use the advertising identifier or track you across apps. We use this only to measure our own advertising. Legal basis: legitimate interest (Art. 6(1)(f) GDPR).

Support emails

If you email us, we receive your email address and whatever you write, and use them only to answer you. We keep support conversations for as long as needed to help you and then delete them. Legal basis: legitimate interest in answering your request (Art. 6(1)(f) GDPR).

Things you share yourself

Tervy lets you share a month card or export your data as a CSV or JSON file through the iOS share sheet. What you share, and with whom, is your choice, and is then handled by the app or person you share it with.

3. The website

The website tervy.app does not use cookies and does not show ads. The waitlist is described in section 2. Our hosting provider (Vercel) processes standard server logs, such as IP address, browser type and the pages requested, to deliver the site and keep it secure. If we measure visits, we use PostHog in cookieless mode without creating personal profiles: we count page views and taps on the App Store button, together with the referring website and your general locale. Legal basis: legitimate interest (Art. 6(1)(f) GDPR).

Launch waitlist

Before Tervy is on the App Store, you can leave your email address on the website to hear when it launches. We store your email address, the time you signed up, which button you used and your language. We use it only to send you one email when Tervy is available, never for a newsletter or advertising, and we never share it. The list is stored with Upstash, a database provider, in the European Union. We delete the whole list within 30 days of sending the launch email. To stop automated sign-ups, we also keep a one-way hash of your IP address (not the address itself) for one hour, to limit how many sign-ups can come from one connection. You can ask us to remove your address earlier at any time by emailing support@tervy.app. Legal basis: your consent (Art. 6(1)(a) GDPR), which you can withdraw at any time.

4. Service providers

Where data is transferred outside the European Economic Area, the transfer relies on the EU–US Data Privacy Framework where the provider is certified, or on the European Commission's Standard Contractual Clauses.

5. How long data is kept

• On-device data: until you delete it. Deleting a change removes its records; "Erase everything" in Settings removes all Tervy data from the app; deleting the app removes it from the device.
• Analytics events and onboarding recordings: kept for up to 24 months, then deleted.
• Purchase records: kept by RevenueCat and Apple for as long as needed to provide your purchases and meet legal (for example tax) obligations.
• Support emails: as long as needed to resolve your request.
• Waitlist emails: deleted within 30 days of the launch email.

6. Your rights

Under the GDPR and similar laws you have the right to access, correct, delete or export your personal data, to restrict or object to its processing, and to withdraw any consent you gave. Most of your data never reaches us, so you control it directly in the app:

• Export: Settings → Export gives you every change, answer, amount, rating, note and tag, plus the daily Health values, as CSV or JSON.
• Delete: Settings → Erase everything deletes all app data and resets the analytics identifier.
• Health access: change or revoke it at any time in the Health app or iOS Settings.

For analytics or purchase data, email us at support@tervy.app. Because we don't know who you are, we may ask you for the identifier shown in the app so we can find your data. You also have the right to lodge a complaint with a supervisory authority, in the Czech Republic the Office for Personal Data Protection (uoou.gov.cz), or the authority where you live.

7. Children

Tervy is not directed at children under 16, and we do not knowingly collect personal data from them.

8. Security

Your Tervy data on the device is protected by iOS data protection and your device passcode. Data sent to our service providers travels over encrypted connections (HTTPS).

9. Not a medical service

Tervy is a habit tracker and a personal record. It is not a medical device, and it doesn't provide diagnosis or treatment. See the Terms of Use.

10. Changes to this policy

If we change how Tervy handles data, we'll update this page and the date at the top. For significant changes we'll also tell you in the app.

11. Contact

Jiří Urbášek
Chářovská 60, 794 01 Krnov, Czech Republic
Email: support@tervy.app