Privacy policy
JointSignal · Last updated 29 August 2026
The short version
JointSignal keeps everything on your phone. There is no account, no server, and no analytics. I do not receive your health information — not in summary form, not anonymised, not ever. The app has no code capable of sending it to me.
Everything below is the detail behind that sentence.
Who this is from
JointSignal is made by Scott Haines, in New Zealand. I built it to track my own rheumatoid arthritis, and I use it every day for the same purpose you do.
What JointSignal records
Only what you enter:
- Daily ratings — pain, how you are overall, fatigue, morning stiffness, sleep, mood, and whether it was a flare day
- Joint counts you tap in yourself
- Weekly function questions
- Medicines, doses and whether you took them
- Blood test results and blood pressure readings you enter
- Appointments, side effects, notes, and questions for your specialist
A question you skip stays unanswered. The app never fills in a blank for you.
Where it is stored
In a database inside the app on your device. That is the only copy, unless you make another one deliberately.
What leaves your phone
Nothing, unless you send it.
JointSignal contains no networking code at all. It cannot transmit your data, because there is nothing in it that could. There is no account to sign in to, no server to sync with, and no third-party code of any kind — no analytics, no crash reporting, no advertising or tracking libraries.
Four things can move data off your device, and all four are things you do:
A backup you export. A single file you share wherever you choose. It goes where you send it.
An automatic backup. Once a day, JointSignal writes a dated backup file to your own iCloud Drive, or to your device if iCloud is not available. Thirty are kept, so a mistake is recoverable. That file sits in your iCloud account under Apple's terms — I have no access to it. You can turn this off in Settings → Backup.
A report you share. When you export a PDF for your specialist and send it by email, message or AirDrop, it carries your health information into whatever you sent it through. That is outside the app's control, so please think about where it is going, particularly over email.
An email you send me. Settings → Send feedback opens your own email app with a message addressed to support@jointsignal.app. It arrives pre-filled with the app's version and build number, your iOS version and your device model — enough to trace a fault to a particular build — and with nothing at all from what you have recorded. No entry, no rating, no joint count, no medicine, no blood result. You write the message and you send it; the app sends nothing itself, and you can delete any of the pre-filled text before you do.
Apple Health
If you allow it, JointSignal reads from Apple Health to show your own activity alongside your symptoms: steps, flights climbed, exercise minutes, walking speed, walking asymmetry, double support time, step length, stair ascent and descent speed, six-minute walk distance, resting heart rate, heart rate variability, sleep, and blood pressure.
The app requests no write access at all. It cannot add to or alter your Health record, by design. Health data is used only to show you your own information and to include it in a report if you export one. It is never sent anywhere and never used for advertising or any other purpose.
You can stop the app reading Health at any time, either in the app under Trends, or in iOS Settings → Privacy & Security → Health. Turning it off in the app stops JointSignal reading and drawing that data; only iOS Settings can withdraw the permission itself, and the app says so where it offers the choice.
Reminders
Reminders are scheduled on your device. There is no push server, and no notification is ever sent from anywhere else.
Subscription and payment
If you subscribe, Apple handles the entire transaction. I never see your card details, your billing address, or your Apple Account. Apple provides me with anonymised sales and subscriber totals — numbers, not people — and nothing in that reporting is connected to anything you record in the app.
If your subscription ends, your record remains yours. You keep full access to read and export everything you have entered. Your symptom history is not held hostage to a payment.
Children
JointSignal is not designed for or directed at children.
Your data is yours
Because I hold none of it, there is nothing for me to hand over, correct or delete on your behalf — and no request you need to make. Everything is on your device: you can read it, export it, or remove it entirely by deleting the app. Deleting the app removes the database with it, so export a backup first if you want to keep your history.
If you are in New Zealand, the Privacy Act 2020 applies to me as a New Zealand developer. If you are in the United Kingdom or the European Union, the UK GDPR and GDPR apply. Under all of them, the position is the same: I am not collecting, processing or storing your personal information.
Changes to this policy
If the app ever changes what it does with data, this page changes with it, before the change ships. The date at the top tells you when it was last revised.
Contact
Questions about this policy, or about anything to do with your data: privacy@jointsignal.app
Anything else — problems, suggestions, or a question about how the app works: support@jointsignal.app
JointSignal records what you tell it and shows you the patterns. It does not diagnose anything and it is not medical advice. Your rheumatologist does the rest.