Last updated: 2026-10-14
SipWiser is published by Christophe Pecsteen, a sole trader registered in Belgium, who is the data controller for the processing described here ("we", "us").
Your sips, sessions, goals, quick logs, profile and settings are stored only on your device. We receive none of it. The only exceptions are things you choose to send us: feedback (§3.9) and newsletter sign-ups (§3.10).
You sign in with Google or, on iPhone, Apple. We receive your email address, the name your provider shares (Apple asks you first), a user ID, which provider you used, when you accepted the Terms, and when you last signed in. We use this to authenticate you and attach your data to your account.
If you turn on BAC estimation, the app asks for your date of birth, sex, weight and height. Combined with your sip history, these reveal information about your health, so we treat them as special-category data (GDPR Art. 9). We process them only with your explicit consent, which you give in a dedicated consent screen before BAC turns on. We record when you consented.
For each drink: time, drink type, size, alcohol by volume, optional notes and tags. We also store your sessions, goals and challenges, quick logs, cocktail recipes, and app settings (units, region, time zone, theme, BAC thresholds, reminder preferences). When you're signed in, these are synced so the app works across devices.
If you turn on location, the app records the coordinates where each sip is logged, only while the app is open, and syncs them with that sip. It powers the "Where you drank" map. On Android the map is drawn by Google Maps, on iPhone by Apple Maps. Location is never included in the personal data API (§3.8).
If you enable reminders, we store a push token for your device. The token is removed when you sign out. To decide whether a reminder is due, our server reads your reminder settings, time zone and when your last sip was. Reminders are delivered through the Expo push service, which passes them to Apple or Google. They contain only a fixed sentence, never your data. We keep a log of sent reminders for 7 days to avoid duplicates. Notifications shown during a live session (including the iPhone Live Activity) are generated on your device.
Purchases are made through Google Play or the App Store. We never see your payment details. RevenueCat manages subscription status for us. It receives an anonymous ID and, once you sign in, your SipWiser user ID, plus the products you bought and their dates. Your Plus expiry date and any supporter status are mirrored to your profile. When you're signed in, we also record when a Plus or tip offer is shown and whether it was dismissed or led to a purchase.
If you create an API token, we store its name, a SHA-256 hash of it (never the token itself), a short prefix, and when it was created and last used. A token unused for 180 days stops working. To prevent abuse we count requests per token, and failed attempts per IP address, stored only as a salted hash and deleted within an hour.
When you send feedback, from the app or this website, we store your message, its category, an optional reply email (if you're signed in, your account email is used), your user ID if signed in, a random device identifier, a salted hash of your IP address, and technical details shown to you before you send: app and OS version, device model (such as "Google Pixel 7" or "iPhone", never the name you gave your device), language, region, units, and which features were on. We copy the message and these details into Linear, the tool we use to track issues.
If you sign up on this website, we store your email address and when you signed up. We use it only to tell you about SipWiser news, such as new features or the iPhone launch. To stop sign-up abuse we keep a hash of your IP address for one hour. The newsletter isn't linked to your app account. Every newsletter includes a one-click unsubscribe link, or you can email contact@sipwiser.app. Unsubscribing deletes your address from the list.
The website uses no cookies, analytics or third-party scripts. Our host, Vercel, processes your IP address and request details to deliver pages and protect the service.
If you pair a Wear OS watch, your phone sends it what it needs to display your live session (BAC estimate, curve, sips in the session) over Google's Wearable Data Layer. This happens between your devices. It doesn't pass through our servers and doesn't include location.
| Processing | Legal basis (GDPR) |
|---|---|
| Account, sync of sips, sessions, goals and settings, Plus and tips, API tokens | Art. 6(1)(b): necessary to provide the service you asked for |
| BAC profile combined with sip history (health data) | Art. 9(2)(a): explicit consent |
| Location, reminders, newsletter | Art. 6(1)(a): consent |
| Feedback, paywall and tip events, security logs, rate limiting, website hosting | Art. 6(1)(f): legitimate interest in running, securing and improving the service |
| Purchase records | Art. 6(1)(c): legal obligations (accounting and tax) |
Where we rely on legitimate interest, the processing is limited, non-personalised and expected for an app like this. You can object at any time (Art. 21) by emailing us.
Withdrawing consent doesn't affect processing that already happened.
Processors (acting on our instructions, under a data processing agreement):
Independent controllers (under their own privacy policies, when you use the related feature):
Some of these providers are based in, or use sub-processors in, the United States. Those transfers rely on the EU–US Data Privacy Framework where the provider is certified, and otherwise on the European Commission's Standard Contractual Clauses. Your synced app data itself is stored in the EU.
You can ask to access, correct or erase your data, restrict or object to its processing, and receive it in a portable format. Much of this is self-serve: Settings → Account → Delete account erases your data, and Plus members can download it as JSON and CSV from Settings → Account → Download your data. Anyone can get a free copy of their data, or exercise any other right, by emailing contact@sipwiser.app. We reply within one month (extendable by two months for complex requests, with notice).
You can also complain to a data protection authority. In Belgium that is the Autorité de protection des données / Gegevensbeschermingsautoriteit: www.dataprotectionauthority.be.
SipWiser is for adults: at least 18, or the legal drinking age where you live if that is higher. We don't knowingly process data about minors. If you believe a minor is using SipWiser, contact us and we'll delete the account.
None. BAC estimates, goals, findings and badges are calculated for your information. They make no decisions with legal or similarly significant effects (GDPR Art. 22).
Data is encrypted in transit and at rest by our providers and protected by access controls and row-level security. If a breach is likely to put your rights at risk, we will notify the Belgian authority within 72 hours and tell you without undue delay if the risk is high (GDPR Art. 33–34).
If we change this policy in a meaningful way, we'll tell you in the app before the change applies. The date at the top always shows the current version.
Questions or requests: contact@sipwiser.app.