Cairn Privacy Policy

Cairn is a private diary for people living with fibromyalgia. It helps you notice patterns and talk to your doctor. This policy explains what the app does with your information, and the short version above is the whole of it: your health information stays on your device, encrypted, and is never sent to us or anyone else.

Who we are

Cairn is published by Senuna, United Kingdom. Contact: senuna.app@gmail.com.

What the app handles, and where it stays

All of the following is stored locally on your device in an encrypted database, and never leaves it except where you explicitly choose (see Sharing, below):

• Profile: the first name you choose (optional), your date of birth (optional, used to show your age on the report), the condition(s) you live with, and whether you have a diagnosis (optional; this only tailors what you read and never changes how the app works).
• Check-ins: pain, fatigue and brain fog ratings, sleep, mood, symptoms and how strong they are, possible triggers, and diary notes.
• Body pain map: the areas you mark, how much they hurt, and the type of pain.
• Pacing: your daily energy budget, the activities and rest you log, and any plans for tomorrow.
• Flares: when they start and ease, how bad they get, notes, and the possible triggers you confirm.
• Medications, reminder times and your notes on how a treatment is going.
• Appointments, prep questions and visit outcomes.
• Settings such as your region, language, reminders and app lock.

We do not collect your email address, location, contacts, photos, or advertising or device identifiers.

Your health data and UK GDPR

Information about your health is “special category” data under UK data protection law. In Cairn it is created, stored and used only on your own device, by you. It is never sent to us, we have no copy of it, and we cannot access, read, correct or delete it. You control it entirely through the app (see Your control, below).

How your data is protected

• Your database is encrypted at rest. The encryption key is held in your device's secure hardware keystore (Android Keystore).
• The app opts out of Android cloud backup and device-to-device transfer, so your data is not copied off the device automatically.
• You can turn on an app lock (fingerprint, face or device PIN) so the app asks you to unlock it before it opens.
• Screenshots and screen recording of the app are blocked, and its content is hidden in the recent-apps view.

Network connections

The app makes only one kind of network request, and it never includes your health data:

• Cairn Premium purchases: subscriptions and the lifetime option are sold through Google Play. Payment is handled entirely by Google under Google's privacy policy; we never see your card or payment details. The app asks Google Play only whether your Google account owns Premium, and keeps that yes/no answer on your device. We have no server, so no purchase information is sent to us, and your health data is never part of a purchase. Free trials, renewals and cancellations are managed in Google Play.

Everything else, including the articles and the app's fonts, is built into the app, so nothing else is fetched from the internet.

Sharing

Nothing is shared automatically. Information leaves your device only when you choose to share or print a Doctor-Ready Report: a PDF you generate. When you tap Share, your device's normal share sheet lets you send it to an app or person you pick; what happens to it after that is governed by that app or recipient.

You can also choose to make a backup: an encrypted file of your Cairn data (ending .fibro) that you create and save yourself (for example to your own Google Drive or email). It is encrypted with a passphrase only you know, using AES-256; without it the file cannot be read by anyone, including us, and we cannot recover a forgotten passphrase. Restoring a backup replaces the data on that phone.

You can also export your data: a readable copy (a JSON file) of everything you have logged, sent through your device's share sheet to an app or place you pick. This file is not encrypted, so anyone who has it can read it.

Notifications, widget and Quick Settings tile

Check-in, medication and appointment reminders are generated and scheduled on your device. Their content is set to private, so details are hidden on a locked screen. The home-screen widget and the Quick Settings tile only open the app (to log a flare or check in) and show none of your data.

Voice notes and the microphone

The check-in offers an optional voice note. If you use it, Android asks for microphone permission the first time. Your words are turned into text by your phone's on-device speech recogniser and added to that day's note. The app never records the sound to a file, never keeps it, and never sends it anywhere. On phones without on-device speech recognition the voice note isn't offered.

Your control

Delete everything: You → Privacy → “Delete all my data” permanently erases all your data from the device, with no recovery. Uninstalling the app also removes it.

Because we hold no copy of your data on any server, there is nothing for us to delete, correct or return on request. Those choices are entirely in your hands, in the app. You can still contact us with any question. If you are unhappy with how we handle anything covered by this policy, you can complain to the UK Information Commissioner's Office (ico.org.uk).

Children

Cairn is intended for adults (18 and over) and is not directed at children.

If we change this policy we will update the effective date above and, where appropriate, note it in the app. If the app ever starts sending any information off your device, this policy will say so before that version is released.

Questions about this policy? Email senuna.app@gmail.com.