Legal
Privacy Policy
Last updated: October 4, 2026
Prevena is a migraine diary for iPhone and Apple Watch. You use it to log attacks, check-ins, sleep and medication, and to see your own patterns. Your health data is sensitive, so this policy explains in plain words what we collect, why, who helps us process it, how long we keep it and how you can delete it.
1. In short
- We collect what you log in Prevena. We read Apple Health data only if you allow it, and only sleep, steps and menstrual flow.
- We never sell your data, and we never use your health data for advertising.
- Your records go to our AI provider, Anthropic, only for the outlook and chat, and only with your explicit consent. Anthropic does not train its models on them.
- Our server and database are hosted by DigitalOcean in Frankfurt, Germany.
- You can disconnect Apple Health and delete your data, or your whole account, at any time.
2. Who is responsible
The data controller for Prevena is Lynex Studio LLC. For any privacy question or request, write to info@prevena.app.
This policy is written to meet the Turkish Personal Data Protection Law No. 6698 (KVKK) and the EU General Data Protection Regulation (GDPR).
3. What we collect
Everything below is tied to a feature you use. We do not collect anything in secret.
Profile
Answers you give when you start: age, gender (optional), name (optional), how long you've had migraine, how often attacks happen, aura, your usual stress and sleep, and your usual bed and wake-up times.
Health records you create
- Attacks, whether logged on your iPhone or on Apple Watch: start and end time, pain level (0 to 10), where it hurts and on which side, symptoms, possible triggers, medicines taken, what helped and your notes
- Daily check-ins: mood, medicines taken that day, symptoms and, if you answer, a range for yesterday's screen time (for example 4 to 6 hours)
- Sleep entries: bed and wake-up times, how well you slept, how often you woke up and daytime naps
- Relief routine sessions: which routine, when, for how long, whether it was during an attack and your rating
- Your medication list and, if you choose to add them, cycle details (start of your last period, usual cycle length, regularity)
- Journal entries and the messages you write in the AI chat
Apple Health data
Only with your permission: daily summaries of sleep, steps and menstrual flow. Section 4 explains exactly how this is handled.
Device and usage data
App version, operating system, device model, language, time zone, region, a device identifier (on iPhone, Apple's identifier for vendor, which lets us find your account again if you reinstall the app), crash reports and usage events (for example which screen was opened). Our analytics provider, Amplitude, also receives your IP address and uses it to work out your approximate city and country. We need these to run the app and fix problems.
Location
Only if you allow it: your phone's approximate location, used to look up the weather. Our server passes rounded coordinates to the weather service and does not save your location to your account. Web server logs, which can include the approximate location used for weather, are kept for 14 days.
Purchases and support
Subscription status and purchase details from the App Store (through RevenueCat), and the emails you send us.
4. Apple Health and Apple Watch data
This section covers the data Prevena reads from Apple Health, including what your Apple Watch records there, and the health records you create on Apple Watch.
What we read, and only with your permission
When you connect Apple Health, iOS asks which data you want to share. You can allow some, all or none, and change it later. Prevena can read:
- Sleep: when you went to bed and woke up, time asleep and in bed, and sleep stages if your device records them
- Steps: your daily step count
- Menstrual flow: the days you logged a period and the flow level
For each day we also keep which kind of device or app recorded the data (for example Apple Watch). Prevena reads no other health data and never writes anything to Apple Health.
Why we use it
- To show your sleep and steps next to your migraine log, on the Sleep screen and in Insights
- To fill in your sleep log for you (you can change anything)
- To include sleep and steps in the doctor report you create
- If you agreed to the AI features, to inform your daily outlook, including where you are in your cycle (see below)
How it is handled
- Your phone works out one summary per day, such as total steps or time asleep. The detailed records stay on your phone.
- Only these daily summaries are sent to our server, over an encrypted connection (TLS).
- They are stored on our own server, hosted by DigitalOcean in Frankfurt, Germany, linked to your Prevena account.
AI processing
Values derived from these summaries, for example how many short nights you had in the last week, are sent to Anthropic, our AI provider, only if you have given your explicit consent to the AI features in the app. Anthropic uses them only to prepare your outlook and does not use them to train its models. If you say no, or withdraw your consent later, none of your health data is sent to Anthropic.
What we never do
- We never sell your health data.
- We never use it for advertising or marketing, and never share it with advertising or attribution tools. The Meta SDK in the app never receives health data.
- We never pass it to data brokers or information resellers.
- We never use or share it to decide on credit, insurance or employment.
- We never store it in iCloud.
- No person looks at your health data, unless the law requires it or you ask us for support that needs it.
How you control it
- In iOS: turn any data type on or off in Settings > Health > Data Access & Devices > Prevena, or in the Health app under your profile picture > Apps > Prevena.
- In Prevena: go to Profile > Apple Health and tap Disconnect. If you choose Disconnect and delete, Prevena stops reading, and your health summaries, together with the nights filled in from Apple Health that you never changed, are deleted from our live database immediately. Delete synced data does the same at any time.
- Our daily backups keep a copy for at most 14 days; after that it is gone for good.
- Nights you logged or changed yourself stay in your sleep log until you delete them or your account.
Records you create on Apple Watch and in Prevena
Attacks you log on Apple Watch (start and end time, pain level, side) are sent from the watch to our server over an encrypted connection; if there is no connection, they wait on the watch and are sent later. These attacks, your sleep entries, your relief routine sessions and the screen-time range you report in a check-in count as health data: we protect them in the same way and never use them for advertising. Your answer to the AI consent question, and when you gave it, is also kept so we can respect it (see Section 6).
5. How we use your data
We use your data only to:
- keep your attacks, check-ins, sleep, routines and journal, and show them back to you
- show your daily outlook and, once there is enough data, possible links between your attacks and things like sleep (the outlook needs your AI consent)
- count your medication days over the last 30 days and suggest talking to your doctor when they add up
- answer you in the AI chat, if you agreed to it
- create the PDF report you ask for
- send the reminders you turn on (they are scheduled on your phone)
- check your subscription and answer your support requests
- keep the service secure, fix errors and understand which features are used
We do not sell your data and we do not use your health data for advertising.
6. AI features and your consent
The daily outlook and the chat assistant use Claude, an AI model made by Anthropic. The chat is always labelled as AI. Version 3.0 of the app asks once for your explicit consent before anything is sent to Anthropic. You can change your answer any time in Profile > AI features, and once you switch to No, nothing more is sent.
If you agree, the following is sent when your outlook or a chat reply is prepared:
- your attack records and notes
- your daily check-ins (including the screen-time range, if you answered it), your journal and your medication list
- your cycle details (such as the start of your last period and your usual cycle length), your other profile answers (such as age) and the weather where you are
- what you write in the chat
- the sleep nights you log yourself (bed and wake-up times)
- your ratings of relief routines (whether a routine helped)
- signals derived from your Apple Health data, if you connected it (for example how many short nights you had this week)
If you say no, logging, the doctor report, relief routines and sleep tracking keep working; only the outlook and chat stay off.
Anthropic processes this data only to prepare your outlook and replies and does not use it to train its models. AI output can be wrong. It is not medical advice, and the outlook never gives a percentage or a date for an attack.
Versions of the app before 3.0 do not ask this question separately and send the same records, without Apple Health data, to prepare the outlook and chat. Updating the app lets you choose.
7. Legal basis
We process your health information on the basis of your explicit consent (KVKK Article 6, GDPR Article 9(2)(a)). Prevena asks for three separate consents, and you can withdraw each one on its own:
- Your health information: from version 3.0, the welcome screen asks you to agree, before you enter anything, to Prevena storing and processing the health information you log as this policy describes. If you started with an earlier version, a one-time Privacy update screen asks you the same when you first open 3.0. To withdraw this consent, delete your account (Profile > Delete My Account).
- The AI features (optional): a separate question decides whether anything is sent to Anthropic for the daily outlook and the chat. To withdraw it, turn AI off in Profile > AI features; nothing more is sent from then on.
- Apple Health (optional): iOS asks for its own permission before Prevena reads anything. To withdraw it, turn the data types off in Settings > Health > Data Access & Devices > Prevena (or in the Health app), and use Disconnect and delete in Prevena to remove the summaries already sent.
We process subscription data to perform our contract with you (KVKK Article 5(2)(c), GDPR Article 6(1)(b)), and technical and security data on the basis of our legitimate interest in running a secure, working service (GDPR Article 6(1)(f)).
Advertising measurement through the Meta SDK relies on your permission: on iOS, the advertising identifier is used only if you allow tracking when iOS asks.
Withdrawing your consent does not affect processing that took place before.
8. Service providers
These companies process data for us only to provide their service, under data processing terms. Apart from Anthropic (and only with your AI consent), none of them receives your health records or your Apple Health data.
- DigitalOcean (data centre in Frankfurt, Germany): hosts our server, database and backups
- Anthropic (United States): prepares the outlook and chat replies, only with your AI consent; does not train on your data
- Open-Meteo: weather data; our server sends it rounded coordinates, never your identity
- RevenueCat (United States): subscription status; receives your random Prevena user ID and purchase details
- Apple (App Store) and Google (Google Play): payments for subscriptions
- Amplitude (United States): usage analytics; receives events such as a screen being opened or an attack being logged, with counts and yes or no values, and your IP address, which it uses to estimate your city and country; never what you write, and never health values such as pain level, sleep times, steps or cycle data
- Sentry (United States): crash and error reports from the app and this website; health values are removed before a report is sent
- Meta Platforms (the Meta SDK in the app): measures which ads lead to installs, trials and purchases; never receives health data
- ImprovMX and Google (Gmail): deliver the emails you send to info@prevena.app
9. Where your data is stored
Our server and database are in the European Union (Frankfurt, Germany). Some of the providers above are in the United States. Data goes to them only as described in Section 8, based on your explicit consent and on the safeguards the law requires, such as standard contractual clauses or, where it applies, the EU-U.S. Data Privacy Framework.
10. How long we keep data
- Your records stay while your account exists, so you can see your history and create reports.
- Apple Health summaries are deleted as soon as you choose Disconnect and delete or Delete synced data.
- Deleting your account in the app removes your data from our live database within 24 hours and from backups within 14 days. If you ask us by email instead, we act on it within 30 days.
- Purchase records are kept for accounting in anonymous form, with no link to you or your account.
- Our server keeps daily backups for 14 days, and they are used only to restore the service after a failure.
- Web server logs, which can include the approximate location used for weather, are kept for 14 days.
- Error reports and usage events are kept by Sentry and Amplitude for a limited period, under our settings with them.
- Records we must keep by law, if any, are kept for as long as the law requires.
11. Security
- All traffic between the app, the watch, this website and our server is encrypted (HTTPS/TLS).
- On your phone, your Prevena identifier is kept in the iOS Keychain.
- The database only accepts requests that carry our server's credentials; the admin tools need a password or a secret token.
- Access to production systems is limited to the people who run Prevena.
No system is perfectly secure. If you notice a security problem, please tell us right away at info@prevena.app.
12. Your rights
Under KVKK Article 11 and GDPR Articles 15 to 22 you can:
- find out whether we process your data and ask for information about it
- learn why we process it and whether it is used for that purpose
- know who we transfer it to, in Turkey or abroad
- ask us to correct incomplete or wrong data
- ask us to delete it
- object to a result that affects you and comes only from automated analysis
- claim compensation for damage caused by unlawful processing
- receive your data in a portable format (GDPR)
- withdraw your consent at any time
Write to info@prevena.app; we answer free of charge within 30 days. You can also complain to a data protection authority: in Turkey the Personal Data Protection Authority (KVKK), in the EU the authority in your country.
13. Deleting your data and your account
- Apple Health data only: Profile > Apple Health > Disconnect > Disconnect and delete. It is deleted from our live database immediately.
- Your whole account: Profile > Delete My Account. Deleting your account in the app removes your data (profile, attacks, check-ins, journal, sleep entries, routine sessions, health summaries, chat history and outlooks) from our live database within 24 hours and from backups within 14 days.
- You can also email info@prevena.app from any address; we may ask you to confirm from the app, and we act on email requests within 30 days.
- Deleting the app from your phone does not delete your account.
- Reports you saved or shared yourself, for example a PDF you sent to your doctor, are outside our control.
14. Children
Prevena does not knowingly collect data from children under 13. Users aged 13 to 18 need the consent of a parent or legal guardian. If you learn that we hold data from a child under 13, tell us at info@prevena.app and we will delete it right away.
15. Medical disclaimer
Prevena is not a medical device. It does not diagnose, treat or prevent any condition and does not replace a doctor. The outlook, possible links, medication-day counts, relief routines and AI replies are for information only. Talk to your doctor about decisions on your health.
In an emergency, call your local emergency number (112 in Turkey and the EU).
16. Changes to this policy
When we change this policy, we update the date at the top. If a change is significant, we also tell you in the app.
17. Contact
- Company: Lynex Studio LLC
- Email: info@prevena.app