Privacy Policy

Last updated: June 8, 2026

This Privacy Policy explains how CaffIQ ("CaffIQ", "we", "us", "our") handles your information. It applies both to the CaffIQ mobile app and to the caffiq.app website.

CaffIQ is a caffeine tracker for iPhone, developed by Guillaume Brard, an independent developer based in France. We designed CaffIQ to be private by default: the information you log stays on your device, and we keep what we collect about you to a strict minimum.

This English version is the reference version. Translations are provided for convenience; if there is any conflict, the English text prevails, without depriving you of the mandatory protections of the law of your country of residence.

The short version

• Your caffeine entries and your profile live on your device (and, if you turn on iCloud, in your own private Apple iCloud account). We cannot see them.
• We use anonymous, aggregated product analytics (PostHog, hosted in the EU) to understand how the app is used and improve it.
• Subscriptions are handled by Apple and RevenueCat — we never see your card details.
• We do not sell, rent, or share your personal data, and we do not track you across other apps or websites.

The caffiq.app website

The website is a set of static pages hosted by OVH in France. It sets no cookies, runs no analytics or tracking, contains no forms or accounts, and does not ask you for any personal data. Like any website, our host processes standard technical connection logs (which can include your IP address) for the limited purposes of delivering the pages and keeping the service secure. Because the site uses no trackers, no cookie banner is required.

Data stored on your device (the app)

The information you enter and generate in the app is stored locally on your iPhone:

• Your caffeine entries (date and time, amount in milligrams, beverage type) and your history.
• Your profile and the settings used to personalize the model — for example your sex, age, body weight, caffeine sensitivity, smoking status, hormonal status, meal schedule and bedtime, plus any optional advanced settings you choose to provide to fine-tune the model's accuracy.
• Your in-app preferences (notification choices, display options, and so on).

The most sensitive fields (such as your age, body weight, and an email address if you provide one for the newsletter) are stored in the device Keychain, Apple's encrypted secure storage. Other data is stored in the app's local database, protected by your device encryption.

We cannot access this on-device data. You stay in control of it and can review or delete it directly in the app, or remove all of it by uninstalling the app.

Health-related data

Some of the information above is health-related data, which receives special protection under data protection law (Article 9 GDPR). You provide it yourself, and you do so to use CaffIQ's personalization features. This data is processed only on your device and, if you enable iCloud, in your own private Apple iCloud account. It is never transmitted to us, and we never have access to it. The legal basis is your explicit consent, given when you enter this information; you can withdraw it at any time by editing or deleting the data in the app.

iCloud sync

If you are signed in to iCloud and enable sync, your CaffIQ data is synchronised across your own Apple devices through Apple's iCloud (CloudKit), in your private iCloud account. This sync is optional and under your control. The data remains governed by Apple's iCloud terms and privacy policy; we have no access to your iCloud content.

Apple Health (HealthKit)

With your explicit permission, CaffIQ can interact with Apple Health:

• It reads the data needed to personalize its estimates: your sleep analysis, and — where you allow it — your date of birth (to derive your age) and your body weight.
• It writes the caffeine intake you log, so it appears in Apple Health alongside your other data.

Apple Health data is processed on your device to power CaffIQ's features. We do not receive it, sell it, share it, or use it for advertising. You can review or revoke Health permissions at any time in the iOS Health app. The legal basis is your explicit consent.

Analytics — PostHog (EU)

To understand how CaffIQ is used and to improve it, we collect anonymous, aggregated usage events (for example, which screens are opened or which features are used) using PostHog, configured on EU-based hosting. These events are tied only to a pseudonymous, app-generated identifier; the limited technical properties we attach are whether you have a Pro subscription, your app language, your app version, and your operating-system version. We do not send your name, your email, or your health or caffeine data to analytics, we do not use advertising identifiers (IDFA), and session replay is disabled. The legal basis is our legitimate interest in measuring and improving the app in a privacy-preserving way.

Subscriptions — Apple & RevenueCat

CaffIQ is free to download and includes core tracking. CaffIQ Pro unlocks the full experience as a monthly or annual auto-renewing subscription, or as a one-time "Lifetime" purchase.

• Payment is processed entirely by Apple. We never receive or store your payment-card details.
• We use RevenueCat to manage subscription status (for example, whether your trial or subscription is active). RevenueCat processes a pseudonymous identifier and your purchase information on our behalf.

The legal basis is the performance of our contract with you (providing the subscription you bought) and compliance with our legal and accounting obligations.

Notifications

If you enable them, CaffIQ sends local notifications on your device (for example reminders, insights, or trial-related reminders). You can turn notifications on or off at any time in the iOS Settings. Where a notification is delivered remotely, it is sent through Apple's notification service and does not carry your personal content. The legal basis is your consent.

Optional feedback and newsletter

If you choose to send feedback from within the app, or to sign up for the newsletter, the message you write — and, for the newsletter, the email address you provide — is sent to our processing endpoint so we can read your feedback or add you to the list. This only happens when you decide to do it. The legal basis is your consent; you can ask us to delete this information at any time.

App install measurement

CaffIQ may use SKAdNetwork, Apple's privacy-preserving framework for measuring app installs. It reports aggregated, coarse information to Apple and does not identify you or use an advertising identifier.

What we do not do

• We do not sell or rent your personal data.
• We do not track you across other apps or websites, and we do not use advertising identifiers (IDFA).
• We do not show third-party ads.
• We do not operate an account system: there is no CaffIQ login, and we do not ask for a password.

International data transfers

PostHog analytics are hosted in the European Union. RevenueCat may process data outside the EU (including in the United States); where that is the case, transfers are covered by appropriate safeguards such as the European Commission's Standard Contractual Clauses. Apple and iCloud transfers are governed by Apple's own policies and safeguards.

Data retention

• On-device data (and iCloud data) is kept until you delete it in the app or uninstall the app.
• Anonymous analytics are kept only as long as needed to improve the app.
• Subscription records are kept as required to provide the service and to meet our legal and accounting obligations.
• Feedback and newsletter data is kept until you ask us to delete it or unsubscribe.

Your rights (GDPR)

If you are in the European Economic Area (and similarly under comparable laws elsewhere), you have the right to access, rectify, erase, restrict, or object to the processing of your personal data, and the right to data portability. Because your CaffIQ content is stored on your device, you can review or delete it directly in the app, or by uninstalling it. For any request concerning the limited data we process (analytics, subscription, feedback, newsletter), contact us using the details below — we respond within the legal time limits.

You also have the right to lodge a complaint with your local data protection authority. In France, this is the CNIL (www.cnil.fr).

Children

CaffIQ is not directed to children and is not intended for use by anyone under the age required by the law of their country to consent to the processing of personal data (for example, 15 in France).

Changes to this policy

We may update this Privacy Policy from time to time. The "Last updated" date above reflects the latest version, and we will announce material changes in the app or on the website.

Contact and data controller

For any privacy question or request, contact us at contact@caffiq.app.

Data controller: Guillaume Brard — Entrepreneur individuel (EI) — France. Full publisher details are set out in our Legal Notice.