Privacy

Last updated: 1 October 2026

This notice explains how Flint — our website at flintfix.com and the Flint app — handles your information. Flint is a reference and diagnostic tool for professional heating engineers.

Who we are

Flint is operated by OnSpec Software Ltd, a company registered in England and Wales (company no. 17328057), trading as Flint. We are the data controller. You can reach us at support@flintfix.com.

The website (flintfix.com)

Our marketing site is static and has no accounts or sign-up forms. Two things measure you here, and both are switched off until you accept them. Google Analytics tells us which pages people actually use. A Meta (Facebook) pixel tells us whether one of our own ads brought you here, and Meta can use what it records to measure and target the ads we run on Facebook and Instagram. Nothing is measured on your first visit unless you say yes, the Meta script is not even loaded until then, and you can change your mind whenever you like using the link below. Separately, if you arrive from one of our own ads, we keep the campaign name from the link in your browser for the length of your visit and pass it on if you go to the app, so we know which ad brought you. That is our own record of our own advertising, it is cleared when you close the tab, and it is not shared with anyone. Our hosting provider records standard server logs (such as your IP address, browser type and the pages requested) for security and reliability. Fonts are loaded from Google Fonts, which may receive your IP address as part of serving them.

Change your cookie choice

The app — what we collect

• Your account. When you create an account we store your email address and, if you choose to provide them, your display name and Gas Safe registration number. You can also choose whether to receive marketing emails.
• Your questions to Ask Flint. When you use the AI assistant, the question you type — and which boiler/manual you're viewing — is processed to generate an answer (see “AI assistant” below).
• Subscriptions. If you subscribe to Flint, payment is handled by the store you subscribed through — the Apple App Store or Google Play in the mobile apps, or Stripe on the web. We never see or store your card details; we keep only your subscription status and the reference that identifies it.
• Feedback and tips. If you send feedback, or submit a fix or tip for a boiler, we store what you send so we can act on it and improve the app.
• Notes and saved boilers are stored on your device, not on our servers.
• Whether one of our Apple ads brought you. In the iPhone app, the first time you open Flint it asks Apple whether you installed it after tapping one of our own ads on the App Store. Apple answers either no, or with which of our campaigns and which of our search terms it was. Apple does not tell us who you are or what you typed, and no tracking identifier is involved, which is why iOS does not ask your permission to track. We keep that answer with your account or subscription so we can tell which of our own ads are worth paying for.
• Which of our ads brought you (Android). When you install Flint from Google Play, Play tells the app which link you came through, for example one of our own Facebook ads. We keep that with your subscription so we can tell which of our ads are worth paying for. It says which of our links you used, nothing about you.
• Telling Meta that one of our ads worked, only if you agree. The first time you open the app it asks whether we may tell Meta (Facebook and Instagram) when you start a trial or subscribe. If you say yes, the app sends Meta that event with the plan and its price, along with a random identifier Meta's software creates for this install, and nothing else: never your name, email, Gas Safe number, boilers, notes or anything you look up. The advertising identifier on your phone is never collected. If you say no, nothing is sent. You can change your answer at any time in Account.

AI assistant (Ask Flint)

Ask Flint answers questions using third-party AI providers — currently Google (Gemini) as the primary provider and Anthropic (Claude) as a fallback. When you ask a question, we send only the text of your question and the relevant manufacturer's manual to the AI provider to generate the answer. We do not send your name, email, account details or Gas Safe number to the AI provider. Answers are reference material for a competent professional and should always be verified against the manufacturer's manual.

Who we share data with

We use trusted service providers (“processors”) to run Flint. They act on our instructions and only for the purposes above:

• Supabase — hosting, database and account authentication.
• Apple Ads: the iPhone app sends Apple a one-off token so Apple can confirm whether the install came from one of our App Store ads. The token identifies the install to Apple, not to us.
• Apple, Google and Stripe — subscription payments. Purchases made in the iOS app are processed by Apple, in the Android app by Google, and on the web by Stripe. Each handles your payment details under its own privacy policy.
• Google (Gemini) and Anthropic (Claude) — processing your Ask Flint questions to generate answers.
• Google Analytics — website usage measurement, and only if you accept the cookie.
• Meta Platforms Ireland: measuring and targeting our own ads on Facebook and Instagram. On the website only if you accept the cookie; in the app only if you say yes when it asks, and then only the trial or subscription event described above.
• Our hosting and email providers, for running the service and replying to you.

We do not sell your personal data. Nothing from your account or from your use of the app is used to advertise to you, and nothing is shared with advertisers. The only advertising measurement we use is the website pixel and the in-app trial and subscription event described above. Both are off unless you agree, and both exist so we can tell whether our own ads are worth running. The iPhone app's Apple Ads check, described above, is our own record of whether our own ads worked.

Legal bases (UK GDPR)

We process your data to provide the app and your account (performance of a contract), and to keep the service secure and working (our legitimate interests). Recording whether one of our own Apple ads brought an iPhone install also relies on our legitimate interest in knowing whether our advertising works; you can object at any time by emailing us. Marketing emails, the website cookies (both the analytics one and the advertising one) and telling Meta about a trial or subscription in the app all rely on your consent, which you can withdraw at any time. Recording which of our own links brought an Android install relies on the same legitimate interest as the Apple ads check above.

International transfers

Some of our providers (including the AI providers) may process data outside the UK and EEA. Where they do, we rely on appropriate safeguards, such as the UK International Data Transfer Agreement or equivalent.

How long we keep it

We keep your account data for as long as you have an account. If you delete your account we remove your personal data, except where we must keep certain records to meet legal obligations — for example, payment and tax records are retained for up to six years. Feedback you have submitted is kept in anonymised form to help improve the app. See deleting your account.

Your rights

You have the right to access, correct, delete or export your personal data, to object to or restrict certain processing, and to withdraw consent. To exercise any of these, email support@flintfix.com. You can also complain to the UK Information Commissioner's Office (ico.org.uk).

Children

Flint is a professional tool intended for adults working in the heating trade. It is not directed at children.

Contact

Questions about privacy, or want a copy of anything here? Email support@flintfix.com.

We may update this notice as Flint evolves; the date above shows the latest version.