Privacy Policy

Effective date: 12 October 2026 · Applies to the Rainu iPhone app (including its widgets and Siri shortcuts) and the website rainu.app.

1. Who we are

Rainu is developed by Gonçalo Baião (WOST), the controller responsible for this policy. Address: [to be completed]. Tax ID: [to be completed].

In practice, Rainu is built so that we don't receive your personal data at all. This policy explains what the app handles on your device and the few limited cases where a third party (Apple or our website host) is involved.

2. What the app processes

To estimate your daily goal and track your progress, Rainu uses the information you choose to enter. All of it is processed on your iPhone.

Some of this, such as pregnancy status, weight and urine checks, can be considered health data. Because it never leaves your device (except to Apple Health, if you choose), it is not collected by us.

3. Where your data is stored

• On your iPhone. Rainu stores your data locally in the app's private storage.
• Shared with Rainu's widgets. A private App Group container on your device lets the widgets and Siri shortcuts show your progress and log drinks. It's not accessible to other developers' apps.
• Your device backups. Like other app data, it may be included in your iCloud or computer backups, under your Apple account and Apple's terms.
• iCloud sync (future). Rainu 1.0 does not sync through iCloud. If a later version adds sync, your data will be stored in your own private iCloud database (CloudKit), which only your Apple account can access. We cannot read it. This policy will be updated before that happens.

4. Apple Health

Using Apple Health with Rainu is optional, and you choose exactly what to allow.

• What Rainu writes: dietary water for each drink you log, and dietary caffeine for coffee. If you undo or delete a drink in Rainu, the matching Health entry is deleted too.
• What Rainu reads: your body weight and exercise minutes, only to pre-fill your profile and estimate your goal. Rainu does not read water logged by other apps.
• Health data is used only to provide Rainu's hydration features. It is never used for advertising or marketing, never sold, never shared with third parties, and never sent to us or any server.
• Rainu does not store Health data in iCloud.
• You can change or revoke access at any time in the Settings app → Health → Data Access & Devices → Rainu (or in the Health app → your profile → Apps). Saying no doesn't limit any of Rainu's features.

5. Notifications

Reminders are local notifications scheduled on your iPhone. They are not sent from a server and no push token is created. You can turn them off in Rainu or in Settings → Notifications → Rainu.

6. What we don't do

• No account, sign-up or login.
• No analytics, crash reporting, advertising or tracking SDKs, and no third-party code that collects data.
• No tracking across apps or websites, and no advertising identifier (IDFA).
• No sale or sharing of personal data.

This is why the App Store privacy label for Rainu says "Data Not Collected". If you send us an email, we'll receive your email address and whatever you write, and use it only to reply (see Contact).

Apple may collect information about app downloads and, if you opt in, crash reports and usage statistics shared with developers under Apple's own privacy policy. We only see this in aggregated, anonymous form.

7. This website

• rainu.app uses no cookies, no analytics, no trackers and no third-party embeds. Fonts are served from our own domain.
• The site is hosted by Cloudflare, Inc. As part of delivering the site and protecting it from abuse, Cloudflare processes technical data such as your IP address, browser user agent and the pages requested. This processing is based on our legitimate interest in keeping the site secure and available (Article 6(1)(f) GDPR). See Cloudflare's privacy policy.

8. Children

Rainu is not directed at children under 13 and is intended for adults and teenagers with a parent's or guardian's involvement where required. Under the GDPR as applied in Portugal, the age of digital consent is 13. Because Rainu doesn't collect personal data, we don't knowingly receive data from children. If you believe a child has emailed us, contact us and we'll delete the message.

9. Keeping and deleting data

Your data stays on your device until you delete it. You can:

• Reset everything in Rainu: Profile → Reset data → Reset all data (you'll be asked to confirm).
• Delete the app: deleting Rainu removes its data from your iPhone, including the widget data.
• Delete Apple Health entries: in the Health app, under the water and caffeine data types, or via Settings → Health → Data Access & Devices → Rainu → Delete All Data.
• Backups: data in older device backups is managed by you through iCloud or your computer.

Support emails are kept only as long as needed to help you, and deleted on request.

10. Your rights

Under the General Data Protection Regulation (GDPR) you have the right to access, correct, delete, restrict or object to the processing of your personal data, and to data portability. Since your Rainu data is on your device, you control it directly. For anything we hold (such as an email you sent us), write to us and we'll respond within one month.

You also have the right to lodge a complaint with a supervisory authority. In Portugal this is the Comissão Nacional de Proteção de Dados (CNPD), Av. D. Carlos I, 134, 1.º, 1200-651 Lisboa. If you live elsewhere in the EU, you can contact your local authority.

11. Changes to this policy

If we change how Rainu handles data, for example by adding iCloud sync, we'll update this page and the effective date before the change reaches the app. Significant changes will also be mentioned in the App Store release notes.

12. Contact

Questions about privacy: hello@rainu.app.

Rainu is a wellness app, not a medical device.