Privacy Policy
Effective & last updated: June 9, 2026
Aymen Chihani (“we,” “our,” or “us”) built GainsPrice as a free app
that helps you search or scan supplements and find the cheapest store to buy them
from across EU retailers. This policy explains what information GainsPrice handles,
why, and the choices you have.
No accounts
No ads
No cross-app tracking
Photos stay on your device
1. Information We Collect
Information you provide by using the app
- Search queries. When you search for a product, the text you type is sent to our backend to look up matching products and prices.
- Scanned barcodes. When you scan a product, the barcode is read on your device and only the resulting number (EAN/UPC) is sent to look it up. The camera image itself never leaves your device.
- Your selected country. You choose your country so the app shows stores, currency, and language relevant to you.
Information collected automatically
- Anonymous install identifier. On first launch the app generates a random id (like
gp-xxxxxxxx). It is not Apple’s advertising identifier (IDFA), not your device id, and not linked to your name. We use it as an affiliate “click reference” (so a retailer can attribute a purchase you made through our link) and to operate and protect the service. It resets if you delete or reinstall the app.
- Basic request information. Our backend receives technical data needed to respond, such as your IP address (used transiently for delivery, security, and rate limiting) and the app version.
Processed only on your device (not collected by us)
- Camera and photos. Barcode detection runs entirely on-device using Apple’s Vision framework. Images are never transmitted to or stored by us.
- Your basket, supplement stack, and preferences. Saved locally on your device so the app remembers them; not uploaded to us.
Information we do NOT collect
- No account, name, password, or postal address.
- No precise GPS location — country is the only location signal, and you set it.
- No IDFA and no tracking across other apps or websites (so no App Tracking Transparency prompt).
- No health or medical records — supplement searches are used only to return results, not to build a health profile.
- No third-party analytics, advertising, or crash-reporting SDKs.
Beta waitlist (website only)
If you sign up for the GainsPrice beta on our website (not in the app), we store the email you submit so we can notify you when the beta opens. You can ask us to delete it at any time. This is the only place GainsPrice collects an email, and it is optional.
2. How We Use Information
- Find products and compare prices across stores — including shipping and delivery time — and present the cheapest (and fastest) options;
- Return results relevant to your selected country and language;
- Attribute affiliate purchases so retailers pay the commission that keeps GainsPrice free (Section 5);
- Operate, secure, and debug the service;
- Notify beta-waitlist subscribers when the beta opens (website sign-ups only).
We do not sell your data, build advertising profiles, or make automated decisions that significantly affect you.
3. How We Share Information
We do not sell, rent, or trade your information. We share it only as needed:
- Service providers / processors — the third parties in Section 4, each receiving only what is necessary.
- Legal requirements — if required by law, regulation, legal process, or valid government request.
- Safety — to protect the rights, property, or safety of GainsPrice, our users, or the public.
- Business transfer — as part of a merger, acquisition, or sale of assets; we will note any such change here.
4. Third-Party Services
| Service | Role | What it receives | Policy |
|---|
| Cloudflare | Hosting & infrastructure (backend, catalog, price history) | Request data (IP, query, barcode, country) | link |
| SerpApi | Product & price search (Google Shopping) | Your search query or barcode number | link |
| Awin | Affiliate network | Anonymous click reference on Buy links | link |
| Amazon Associates | Affiliate links to Amazon | Affiliate tag on Amazon links | link |
When you tap Buy, you leave GainsPrice for the retailer’s own site or app, governed by that retailer’s privacy policy — not ours.
5. Affiliate Links & Disclosure
GainsPrice is free and earns commission through affiliate partnerships. This does not change the price you pay.
- Some “Buy” links are affiliate links; if you purchase after tapping one, the retailer may pay us a commission.
- Commission never affects which store we show as cheapest — ranking is the real total cost to you (price + shipping − promotion). A cheaper non-affiliate store is always ranked first.
- As an Amazon Associate, GainsPrice earns from qualifying purchases.
- Affiliate links carry the anonymous install reference (Section 1) — never your name or an account.
See the standalone Affiliate Disclosure.
6. Data Retention
- Anonymous install id: on your device until you delete/reinstall; server-side records keyed to it are short-lived.
- Search queries & barcodes: used to perform your lookup. We may cache the resulting product/price data (about products, not you) to speed up lookups and show price history.
- Request logs (e.g. IP): retained only transiently for delivery, security, and abuse prevention.
- Beta-waitlist email: until the beta launches or you ask us to delete it.
7. Data Security
- Encryption in transit (HTTPS/TLS) for all communication;
- Data minimisation — we avoid personal identifiers by design;
- On-device processing of camera images, so photos never travel over the network;
- Limited access to the small amount of data our backend holds.
No method of transmission or storage is completely secure, but we take commercially reasonable steps to protect your information.
8. Your Rights
- Reset the anonymous identifier by deleting and reinstalling the app.
- Clear local data (basket, stack, preferences) by deleting the app.
- Contact us at chihaniaymen553@gmail.com for any privacy request.
Because GainsPrice is anonymous and holds no account identifying you, we may be unable to locate data about a specific person beyond what is tied to the anonymous identifier or a waitlist email you provide.
European Economic Area / UK (GDPR / UK GDPR)
- Data controller: Aymen Chihani — chihaniaymen553@gmail.com
- Lawful bases: legitimate interests (operating & securing the service, affiliate attribution); consent (optional beta-waitlist email, withdrawable anytime). No profiling or significant automated decisions.
- Your rights: access, rectification, erasure, restriction, objection, portability — email us; we respond within 30 days.
- International transfers: some processors (SerpApi, Amazon, Cloudflare) are outside the EEA, including the US; we rely on safeguards such as EU Standard Contractual Clauses or adequacy decisions.
- Complaints: you may lodge a complaint with your local Data Protection Authority.
California (CCPA/CPRA)
We do not sell or “share” your personal information, and do not use it for cross-context behavioural advertising. Email us to know or delete information associated with you; we will not discriminate against you for exercising these rights.
9. Children’s Privacy
GainsPrice is for a general audience purchasing dietary supplements and is not directed to children under 16. We do not knowingly collect information from children. If you believe a child provided us information, email us and we will delete it.
10. Changes to This Policy
We may update this policy from time to time. For material changes we will update the “last updated” date and post the revised policy here. Continued use after changes constitutes acceptance.
11. Contact Us