Privacy Policy
Last updated 20 October 2026
Stiff is an iPhone app made by GOSUBIT PTY LTD, a company in Australia (“we”, “us”). This policy says what we collect, why, who handles it for us, how long we keep it and how you can see, change or delete it. How we handle health data in particular is also set out in our Consumer Health Data Privacy Policy.
The short version
- Your scan’s video never leaves your phone. The app measures your body positions on the phone and sends only those.
- Your scans, results and plan are used to give you your Move Age, scores and plan, and for nothing else.
- We never sell your data, never use it for advertising and never track you across other companies’ apps or websites.
- Friends see your name, streak, points, level and badges. Never your Move Age, scores, age or scans.
- You can delete your account and everything in it from the app, at any time.
What we collect, and why
Your account
Your email address and a password, or, if you sign in with Apple, the identifier and email address Apple gives us (which can be one of Apple’s private relay addresses). We don’t ask Apple for your name. We use these to sign you in and to send you account emails: sign-up confirmation, password reset, sign-in codes and notices that your account changed. Our sign-in provider stores your password only in a scrambled (hashed) form.
Your profile
The display name you choose, your birth date and your phone’s time zone. Your name is shown to you and to your friends. Your birth date is shown to nobody else: it gives your age on the day of each scan, because your Move Age is measured against your real age. Your time zone decides what counts as a day for your plan, streak and reminders.
Your scans and results
During a scan your phone’s camera films three squats, and the app measures on the phone where your joints are in each frame: 17 body points, how sure it is of each, how many people it saw, the picture’s size, how the phone was tilted and the app’s version. Only those measurements are sent to us. The video stays on your phone and is deleted. From the measurements our server works out your joint angles and squats, your five area scores (ankles, knees, hips, trunk and shoulders), your Move Age and its range, and your 30-day plan. A scan that can’t be measured keeps only the reason it couldn’t.
Your setup answers
When the app asks them: your main goal, how active you are, how long you sit, your tight spots, and how long and when you want to stretch. They shape your plan and your reminders.
Your routines
When you start and finish each routine, the steps you did, how long you were active, the day it counts for, and the streak, points, level and badges they earn.
Reminders
Whether reminders are on, the time we learn from when you usually finish a routine, your phone’s push notification token and which reminders we sent. A reminder can mention your streak, how many routines are left in your plan or how many friends stretched today. It never mentions a score, an age or a friend’s name. In the same way, your friends’ reminders can count you among the friends who stretched today.
Friends
Who your friends on Stiff are and when each friendship began. You add a friend only by sharing an invite link and having them open it. We keep each link only in a scrambled form, so we can’t recreate it, and a link stops working after 14 days. We also count missed and repeated tries, to limit misuse.
Limits
Counts of how often your account has scanned, started routines, made invites or asked to delete, so that one account can’t overload Stiff.
Usage events
A short, fixed list of events tells us where people get stuck, tied to your account id once you’re signed in:
- Stiff was opened for the first time on a phone
- Sign-up started, and whether by email or Apple
- Sign-up finished, and whether by email or Apple
- A scan started filming
- A scan ended, and whether it gave a result, needed a redo or failed
- A result was opened, and whether right after the scan or from history
- A routine started, and which day of the plan it was
- A routine was finished, and which day of the plan it was
- The offer to turn on reminders was shown
- The reminder offer was accepted or declined
- A reminder notification was tapped
- An invite link was shared
- An invite link added a friend
- A second or later scan gave a result
- An account deletion began
- The update-required screen was shown
- A daily limit was reached, and which one
Each event also carries the app’s version and build, your phone’s OS version and device type, the analytics library’s name and version, a random id for this install of the app and one for the current session, and whether you were signed in. No event ever carries a measurement, score, Move Age, age, birth date, name, email address, friend or anything you type. We don’t record screens, taps or your location.
Crash reports
When the app crashes or hits an error it didn’t expect, it sends the error’s type and where in the code it happened, the app’s version and build, and your phone’s model and OS version. Crash reports are not linked to your account. Error messages and anything else about you are stripped from them: on the phone for most errors, and at Sentry, before storing, for the rest.
Your requests to our servers
Each time the app talks to our servers, they see your IP address, and their logs keep it with the time, your device’s software, the country the address is in, your account id and the outcome. We use these logs only to keep Stiff running and secure.
Support emails
What you send us, and our replies.
Our website
trystiff.com uses no cookies, analytics, advertising or content from anyone else. Cloudflare, which serves it, handles your IP address and the request to deliver the page and protect it from attacks. An invite link’s code sits after the “#” in the address, which your browser never sends to a server: the invite page reads it on your phone, and it goes only to your clipboard, if you tap Get Stiff, and to the app.
On your phone
The app keeps your sign-in in the iPhone keychain, an invite you opened for up to 14 days, and a scan’s files until they’re sent and answered (cleared within 1 hour to 7 days). On the first launch after installing, it checks whether the clipboard holds a link, without reading it. Only if it does, it reads that link once, so an invite you copied on our website reaches the app; anything else is ignored.
Health data and your consent
Your scans, results, plan and routines describe your body and how it moves, so we treat them as health data. Before the app asks its first health question or films your first scan, it asks for your consent and explains what it uses the data for; you agree by tapping Agree and continue. You can withdraw your consent at any time in the app (Settings, then Your data) or by emailing us. Withdrawing stops new scans, squat checks and Move Age; past results stay until you delete them. Details are in our Consumer Health Data Privacy Policy.
Stiff is for adults 18 and over. The app asks for your birth date and won’t create a profile for anyone younger. If you think someone under 18 has made an account, email us and we’ll delete it.
Who handles your data
These companies handle data for us, only to provide their service to us:
| Company | What it does for us | What it handles | Where |
|---|---|---|---|
| Supabase | Our database, sign-in, file storage and server code, including the server that turns a scan into your results | Everything in your account, and each request’s IP address | United States |
| Expo | Delivers reminder notifications to Apple | Your push notification token and the reminder’s words | United States |
| Apple | Sign in with Apple, the App Store, and showing notifications on your iPhone | Your Apple sign-in identifier and email, and reminder notifications | United States |
| PostHog | Product analytics: which steps of Stiff people use | Usage events with your account id | United States |
| Sentry | Crash reports | Crash reports, not linked to your account | United States |
| Resend | Sends our emails | Your email address and the email we send you | United States |
| Cloudflare | Hosts trystiff.com and forwards email sent to our support address | A website visitor’s IP address and request; your emails to us | Worldwide network |
Your friends on Stiff see your display name, streak, points, level, rank among your friends, badges and the day you became friends, and their reminders can count you among the friends who stretched today. Someone who opens your invite link sees your display name once they’re in. Nobody else sees anything of yours.
We don’t sell, rent or trade personal information. We don’t share it for advertising, with data brokers, or to track you across other companies’ apps or websites. We would disclose it only if the law required us to, and we would tell you unless the law forbade it.
Where your data is kept
We are in Australia. The companies above keep your data in the United States (Supabase keeps your account in its US database), and some of it passes through their networks in other countries on the way: Supabase can run its server code at the location nearest to you while it works out a scan’s result, and Cloudflare’s network spans the world. We take reasonable steps to make sure each of them protects your data as the Australian Privacy Principles require, and under Australia’s Privacy Act we remain accountable for how they handle it.
How long we keep it
| What | How long |
|---|---|
| Your account, profile, scans, results, plan, routines, reminder settings and friends | Until you delete your account |
| Push notification tokens | Until your phone stops accepting notifications, or 30 days after your phone was last seen |
| Records of reminders sent | 3 days. Your reminder settings also keep the times of the last seven, so we can pause reminders you aren’t opening |
| Usage events | Up to a year at PostHog, and deleted with your account. Events your phone sent before you signed in are linked to your account once you sign in; those from a phone that never signs in are linked to no one |
| Crash reports | 30 days at Sentry. They are not linked to you |
| Emails we send you | 30 days at Resend |
| Server logs | Up to 7 days at Supabase: each request’s time, IP address, country, device software, account id and outcome. Our own code’s log lines add only sizes, durations and a short one-way code made from your account id, never a measurement |
| Our sign-in provider’s security log | The email address, account id, IP address and time of each sign-in event. Deleting your account doesn’t remove these entries yet; email us and we’ll remove them |
| Database backups | Copies of the database we take before each change to it, kept on our team’s computer. The ten most recent, and any from the past week, are kept, and a deleted account stays in them until they’re replaced by newer ones |
| Support emails | As long as we need them to help you and to keep a record of your request |
Deleting your account
In Stiff, open the Profile tab, tap Settings, then Delete account. You confirm with your password, or with Apple if you signed in with Apple. Deleting is immediate and can’t be undone:
- Our server deletes every record and file of your account, then checks that nothing is left before it reports the deletion done. If a step can’t finish at once, it carries on by itself within about 15 minutes.
- If you signed in with Apple, we ask Apple to revoke Stiff’s access to your Apple ID.
- About an hour later we ask PostHog to delete your usage events, and once more a week later for any event that arrived late.
- We keep a record that the account existed and was deleted (its id and the deletion’s progress, nothing else) for about 8 days, to finish and confirm the deletion, and longer only if PostHog has not yet confirmed its part.
- The app removes your sign-in and your scan and routine files from the phone.
Backups, our sign-in provider’s security log and crash reports are as described above. Deleting your account doesn’t cancel an App Store subscription: cancel it in your iPhone’s Settings.
Your choices and rights
You can ask us for a copy of your data, to correct it, to delete it or to stop using it, and you can withdraw your consent to health data at any time. Email support@trystiff.com. We’ll check the request comes from you, never charge for it, and answer within 30 days.
If you live in a US state with a privacy law, you may have rights to access, correct, delete or get a copy of your data, and to opt out of its sale, targeted advertising and profiling. We don’t do any of those three. Email us to use any of these rights. If we turn a request down, you can appeal by replying to our answer; we answer an appeal within 45 days and tell you how to contact your state’s attorney general if you disagree.
Questions and complaints
Email support@trystiff.com, or write to us at our postal address (published here before Stiff is on the App Store). We’ll answer within 30 days. If you’re not satisfied, you can complain to the Office of the Australian Information Commissioner at oaic.gov.au, or to your local privacy regulator.
Security
Everything travels encrypted between your phone and our providers. Each account can read only its own records, your birth date only by you, and the keys that can read every account stay on our servers and one secured computer of ours. Your sign-in on the phone sits in the iPhone keychain. If a data breach is likely to cause you serious harm, we’ll tell you and the Office of the Australian Information Commissioner.
Results worked out by software
Your Move Age, scores and plan are worked out automatically by our software from your scan’s measurements and your age. They are estimates to guide your stretching. They don’t decide what you can do or get, and Stiff isn’t medical advice.
Changes to this policy
We’ll update the date above when this policy changes, and tell you in the app or by email before a change that affects what we collect or why. We’ll ask for your consent again before collecting a new kind of health data or using it for a new purpose.