Privacy policy

Susten builds a weekly meal plan around your goals and maps it to real supermarket products. Doing that well means we hold personal data about you, some of it sensitive. This policy explains what we collect, why, who else touches it, how long we keep it, and the choices you have. It describes what the service actually does today — including the parts still rough at the edges — rather than a generic template.

1. Who we are

The data controller is RS TECHNOLOGY LIMITED, a company registered in England and Wales (company number 17050418), registered office at 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ, United Kingdom. We trade as Susten.

For anything in this policy, contact richard@susten.app. We are registered with the Information Commissioner's Office (ICO), registration reference ZC225155.

2. What we collect

Account details

• Email address and first name.
• Your password, stored only as a secure hash (Argon2id) — we cannot read it. Sign-in and email-verification tokens are also stored hashed.

Goals and body metrics

If you let the app work out your targets: sex, age, weight, height, activity level, and goal (lose, maintain, gain), plus the calorie and macro targets derived from them.

The macro calculator on this website is different. Your age, gender, height and weight stay in your browser, and we never receive them. Our website analytics records only the goal and diet you picked.

Dietary requirements and allergens

Your allergens (for example gluten, dairy, nuts), diets (for example halal, kosher, vegetarian, keto), kitchen equipment, budget, and how you like to cook. Some of this is special category data — see section 3.

How you use Susten

• Your meal plans, recipe customisations, and recipe ratings.
• Order history: what was on the list, its estimated cost, and the delivery date and time window you recorded.
• Free-text notes you attach to recipes. These are stored as you write them, so please don't put anything in a note you wouldn't want stored.

Technical data

• When you register, sign in, or use a sign-in link, we record the IP address and browser identifier (user agent) of the request alongside the session token, for account security.
• Application logs, which can include your email address, kept for 30 days.
• How you use the app: the screens you visit and what you tap, linked to your account by a number. See section 6.
• Recordings of your sessions in the app, with everything you type and your health figures hidden. See section 6.
• Analytics on this website, and whether our ads lead to waitlist signups. See section 6.
• How you found us: if you sign up after following an ad or a campaign link, the campaign's labels and, for a Google ad, a click ID. We keep them with your account. See section 6.

Waitlist

If you join the waitlist we collect your email address and the features you said you were interested in. If you came from one of our ads, we also record which campaign it was, using the labels in the link you followed. That tells us which ads bring people to Susten. It doesn't identify you.

3. Health and dietary data (special category data)

Some of what makes Susten useful is legally sensitive. Allergens can reveal a medical condition. Halal or kosher requirements can reveal a religious belief. Body metrics and weight goals relate to your health. UK GDPR calls this special category data and holds it to a higher standard.

We process it only to build and adjust your meal plans, and only with your explicit consent, which we ask for separately when you create your account (Article 9(2)(a) UK GDPR). We record when you gave it and which version of this policy you agreed to. You can withdraw consent at any time by deleting your account, or by emailing richard@susten.app — though without this data Susten cannot plan around your requirements, so withdrawing it means we can no longer provide the personalised service.

4. Why we use your data, and our lawful bases

We do not sell your data, and we do not use it to target ads at you. There is no profiling that produces legal or similarly significant effects — the only automated decisions are which recipes end up on your plan.

5. Who we share it with

We use a small number of service providers, each processing data on our instructions:

When you click through to Tesco or Sainsbury's, you leave Susten and that retailer's privacy policy applies. We don't send them your data — the link works like any link on the web, which means the retailer's site sees your IP address when it loads, as with any site you visit.

Where a provider processes data outside the UK, we rely on UK adequacy decisions or the UK's approved standard contractual safeguards (the IDTA or UK Addendum).

6. Cookies and analytics

This website uses two analytics tools: Google Analytics, which sets _ga cookies, and PostHog, which sets ph_ cookies. It also uses Google Ads, which sets _gcl_ cookies. These record that you arrived from one of our ads, so Google can tell us whether the ad led to a waitlist signup. We don't let Google use them to show you ads elsewhere.

All of these cookies are off by default and only turn on if you accept them in the banner. Reject them and none are set. Google's script doesn't load until you accept, so until then Google gets nothing from this website. To change your mind, use Cookie settings at the foot of this page.

If you don't accept, PostHog still counts your visit. It keeps nothing on your device, so it can't tell when you come back.

The app uses PostHog too, and stores nothing on your device for it. It records which screens you visit and what you tap, so we can see where the app is hard to use. It also records your sessions. In those recordings, everything you type is hidden, and so are your goals, targets, diet, and allergens. We link all of this to your account by a number, never by your name or email. Your health and dietary data is never sent to PostHog.

When you follow a link from this website into the app, the link carries the number PostHog gave your visit. That lets us see which pages lead to a signup. It stores nothing on your device.

We record your banner choice in your browser's local storage. The app itself stores your sign-in session in local storage too — that's strictly necessary for the service to work and isn't used for tracking. The app sets no advertising cookies.

While you're signed in, the app also sets one cookie, susten_signed_in, that this website can read. It tells this website to show Open app instead of Sign in. It holds no account details and lasts 7 days at most. It's strictly necessary, so it doesn't need your consent, and signing out deletes it.

How you found us

When you follow an ad or a campaign link to Susten, the link names the campaign (for example utm_campaign). A Google ad also adds a click ID (gclid). This website passes them on to the app, and we keep them with your account when you sign up. That tells us which campaigns bring people who go on to plan and shop with Susten.

If you accepted the cookie banner on this website before you went to the app, we send the click ID back to Google Ads. With it go the time you signed up, and the time and total of your first shop. That lets Google count which of our ads lead to signups. Google gets no name, email address or other detail about you. If you rejected the banner or didn't answer it, we don't send anything.

The campaign's labels also go to PostHog with your signup and your orders. The click ID doesn't. You can object to us keeping either: email richard@susten.app and we'll delete them.

7. How long we keep it

8. Your rights

Under UK GDPR you can ask us to:

• Access your data — a copy of what we hold about you.
• Correct anything inaccurate.
• Erase it. You can delete your account yourself from the app (Account → Delete account). This permanently removes your account, profile, plans, and history from our database. Our encrypted backups still hold them for up to 14 days, until the last backup taken before you deleted it expires.
• Export it (data portability). There's no self-serve export yet — email us and we'll send you your data within one month.
• Object to processing based on legitimate interests, or restrict processing while we resolve a dispute.
• Withdraw consent at any time, without affecting processing that happened before.

Two honest caveats about deletion:

• We keep your email address on a do-not-contact list after deletion, so we never email someone who left. That is the only thing we keep.
• Deleting your account does not yet automatically remove your contact record from our email provider (Loops) or the waitlist store. Email richard@susten.app and we'll remove those by hand. We're working on making this automatic.

To exercise any right, email richard@susten.app. If you're unhappy with how we handle your data, you can complain to the Information Commissioner's Office at ico.org.uk, though we'd appreciate the chance to sort it out first.

9. Security

Passwords are hashed with Argon2id and never stored in plain text. Session and sign-in tokens are stored hashed. All traffic is encrypted in transit. Access to production data is limited to the people who run the service.

10. Changes to this policy

When we change this policy we'll update the date at the top, and for significant changes we'll tell you by email or in the app before they take effect.

11. Contact

RS TECHNOLOGY LIMITED, 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ, United Kingdom.
richard@susten.app