Privacy policy

What the Sutra app collects, why it needs it, where it goes, and how to get rid of it.

Last updated 9 September 2026

The short version

We collect what running a gym membership needs and nothing else: who you are, the basics of your body and your goal, and a record of your visits, bookings and programme. The app reads your location so it can tell you have arrived at the club, and — if you allow it — it can do that while the app is in the background, so your visit marks itself without you opening anything. There are no adverts, no analytics kits, no trackers, and nothing is sold or shared with anyone for their own purposes. You can delete the lot from inside the app.

Who this is about

Sutra Hybrid Club is a gym in Bengaluru, Karnataka, India, and publishes the Sutra iPhone app for its members. In the language of India's Digital Personal Data Protection Act 2023, the club is the data fiduciary for everything described here, and you are the data principal. This policy covers the app and the staff dashboard behind it. It does not cover anything you do at the club that never reaches the app.

What we collect, and why

All of it comes from you or from your use of the club — we buy no data and receive none from data brokers.

Account: Your name, and either an email address or a mobile number — whichever you sign up with. It identifies you and is how we sign you in.
Password: Stored only as a PBKDF2-HMAC-SHA256 hash with a random per-account salt and 100,000 rounds. We never hold the password itself, and nobody at the club can read it.
Profile: Date of birth, gender, height, weight, target weight, fitness goal and activity level. Your coach uses these to set a sensible programme, and the app uses them to show progress.
Location: Your precise position, checked purely to work out whether you are at the club. With your permission this check can also run while the app is in the background. See below.
Attendance: The date and time of each visit, how it was marked — by the app checking where you are, by the fingerprint reader at the door, or by staff at the desk — and how far from the club you were when the app marked it.
Fingerprint reader: If you enrol a finger at the desk, the reader stores your fingerprint on the reader itself and gives you an enrolment number. Your fingerprint never leaves that device and is never sent to us. What reaches our server is the enrolment number, the date and time, and whether you were coming in or going out. Enrolling is optional; the app and the front desk both mark attendance without it.
Bookings: Amenity and boxing sessions you book or cancel, personal-training sessions scheduled for you, and any session pack you hold.
Training: The programme and exercises assigned to you, and the workouts recorded against your account.
Bodyweight: Each weight you log, with its date.
Body readings: Height, weight, body fat, muscle mass, body water, bone density, visceral fat, BMI and metabolic age, with the date each was taken. Most are measured on the club's scale by a trainer; some are worked out from the others, and the app marks which. Your fitness-test results — endurance, strength, balance and flexibility — are recorded the same way.
Photographs: Your profile picture, and any progress photographs you add yourself. See Photographs and images below for where they are kept and who can reach them.
Notices: Which club announcements you have seen, and your yes or no when one asks a question — for instance whether you are coming to an event.
Session: A random sign-in token, valid for sixty days and renewed as you keep using the app. It is kept in your iPhone's Keychain, not in ordinary app storage.

Your membership plan, its start and end dates, and your approval status are also held on your account. They are set by staff, not by you.

Location, specifically

This is the most sensitive thing the app asks for, so it is worth being exact.

What we ask for. The app asks iOS for "Always" location. iOS never grants that straight away: it gives "While Using the App" first, and only later offers you the upgrade itself. Whichever you give, the app works — "Always" is what lets your visit mark itself; "While Using" means it marks when you next open the app.
When it reads. At most one position per day, and none at all once the day is already marked. If you have granted "Always", the app also keeps a watch running that only wakes when your phone actually moves 75 metres or more — a phone sitting on a desk produces nothing. It does not read your position while you are asleep, at work, or anywhere else once the day is marked.
What is checked. The reading is sent to our server, which compares it against one point: the club's coordinates. If you are within about 25 metres, the day is marked as attended. If you are not, the reading is rejected and nothing is kept.
What is kept. The distance — a single number in metres — alongside the attendance record. Your latitude and longitude are used for that one comparison and are not stored. There is no trail, no map, and no history of anywhere you have been other than the club.
It is never used for anything else. Not advertising, not analytics, not working out where you live, shop or train instead. It has one job.
Turning it off. Refuse it, or change it to "While Using" or "Never" at any time in iOS Settings → Privacy & Security → Location Services → Sutra. Everything else in the app keeps working, and staff mark your attendance at the desk instead.
If you are staff. Trainers use the same app, and the background check does not run for them at all. Your hours are recorded only when you press the button to start and end a shift.

Photographs and images

Two different things end up in the app, and they are worth separating.

Pictures of the club — the facilities, the offer banners, the notices — are uploaded by staff through the staff dashboard. Nothing about you is in them.

Pictures of you. You can set a profile picture, and you can add progress photographs from the personal-training screen. These come from your iPhone's photo library or its camera, so the app asks for those permissions at the moment you first use one of those buttons. If you say no, everything else in the app carries on working; there is simply no picture. You can delete a photograph you have added, and deleting your account removes all of them.

Where they are kept, and who can reach them. Every image, yours included, is stored in Cloudflare R2 and served over a plain public web address with a long random name in it. That address is not guessable, and it is not listed anywhere — but it is also not password-protected. Anyone you send the link to can open it, and so could anyone who obtained it. Please treat a progress photograph the way you would treat any picture you have put on the open web, and do not put anything in one that you would not want seen.

What we do not do

No advertising, anywhere, ever.
No analytics or attribution kits. The app carries no third-party SDK that reports on you.
No selling, renting or bartering of member data. No sharing with anyone for their own purposes.
No tracking across other companies' apps or websites, and no advertising identifier.
No profiling or automated decisions that affect you. A human at the club approves your membership, sets your programme and decides everything else.

Who can see your data

Club staff. Administrators signed in to the staff dashboard can see your account, profile, attendance, bookings, programme and weight log. That is the point of it — it is how your coach knows what you are doing and how the front desk manages the timetable.

Cloudflare, as our processor. Everything is stored on Cloudflare's platform: the database in Cloudflare D1, images in Cloudflare R2, and the API itself runs as a Cloudflare Worker. Cloudflare holds the data on our behalf and under our instructions; it does not get to use it for its own ends.

Nobody else, unless the law requires it of us — a court order, or a lawful demand from a public authority.

How it is protected

Passwords are hashed, never stored or transmitted in the clear.
Everything between the app and the server travels over HTTPS.
Your sign-in token lives in the iPhone Keychain, which is encrypted at rest and tied to your device passcode.
The server re-checks the attendance rule itself rather than trusting the app, so a modified app cannot claim a visit that did not happen.
The staff dashboard needs an administrator account; ordinary member logins cannot reach any of it.

No system is perfect, and we will not pretend otherwise. If we ever discover a breach affecting your data, we will tell you and the Data Protection Board of India as the Act requires.

How long we keep it

Your account and its records stay while you are a member, because that history is what the club and your coach work from.

If your membership lapses, the app locks you out but the account itself is kept, so that renewing picks up where you left off rather than starting over. We do not currently delete lapsed accounts on a timetable — they are removed when you ask us to, or when the club clears them out. We would rather say that plainly than name a period we do not actually enforce.

Sign-in tokens expire on their own and are cleared as they do. Failed sign-in attempts are kept for a couple of hours, purely to make the rate limit work, and then swept. A write your phone held while it had no signal keeps a short record on the server for two days so that sending it twice cannot record it twice; after that the record goes.

Delete your account yourself and none of that waiting applies — it goes at once.

Your rights

Under the Digital Personal Data Protection Act 2023 you can:

See what we hold. Most of it is already visible in the app; ask and we will send you the rest.
Correct it. You can edit your own profile in the app. Ask staff for anything you cannot reach, such as your plan dates.
Have it erased. Delete your account in the app, or ask us to.
Withdraw your consent — for location, by turning the permission off; for everything else, by deleting your account, since we cannot run a membership without the rest of it.
Nominate someone to exercise these rights for you if you die or become incapable of doing so. Email us and we will record it.
Complain. Write to us first, using the address below. If we have not sorted it out, you can take it to the Data Protection Board of India.

We answer requests at the email address below and do not charge for them.

Deleting your account

In the app, under Profile, there is a delete option. It removes your account, your profile, your attendance history, your bookings, your assigned programme and your weight log from our database. Once it is done we cannot bring any of it back.

You can also email us and we will do it, after checking the request really comes from you. Deleting the app from your iPhone on its own does not delete anything from our side.

A membership is a separate agreement with the club, and deleting your app account does not cancel it or refund it. Speak to the front desk about that.

Children

The club accepts members from the age of 12, and the app will not take a date of birth younger than that.

Under the Act, anyone under 18 is a child, and their data may only be handled with the verifiable consent of a parent or guardian. So for a member under 18 the account is set up at the club, in person, with a parent or guardian present and consenting, and it is the club that approves it — a young member cannot simply register on their own and start using it. No part of the app advertises to anyone, and nothing in it tracks or profiles a member of any age.

If you are visiting from the EU or UK

The club and its data are in India, and Indian law governs this policy. If you are in the European Economic Area or the United Kingdom, the GDPR gives you broadly the same rights described above — access, correction, erasure, objection and portability — and you can exercise them at the same address. Using the app means your data is handled in India.

Changes

If we change what we collect or what we do with it, we will change this page and move the date at the top. Anything significant will also appear as a notice in the app rather than being left here for you to find.

Contact

Questions, requests and complaints about your data all go to the same place:

pavankumar.nagaraj@gmail.com

+91 80953 73737

Sutra Hybrid Club, Bengaluru, Karnataka, India.