Support

Mercek 1.3 · Last updated: 17 September 2026

Frequently asked questions

The product I scanned wasn't found. What now?

Product data comes from open, community-built databases, and not every barcode is registered yet. For a missing product the app suggests adding it: a single photo of the front of the package is enough — we only need to see which product it is, and our team researches and types up the ingredients and nutrition values. Our team also adds the record to Open Food Facts; you don't need an account there.

The product is found and has nutrition values, so why is there no score?

We score products together with their ingredient list. A score based only on sugar and fat, without seeing the additives, would be misleading — a sugary soft drink could come out as "good". Tap "Send a photo of the ingredients" on that screen and photograph the ingredients section on the pack; our team adds the list and the product gets scored.

What is Mercek Pro and how do I cancel it?

Mercek Pro is an optional subscription that shows higher-scoring alternatives in the same category for the product you scanned. It has a monthly and a yearly plan, with a 7-day free trial for first-time subscribers. Scanning, scores, comparison and the ingredient library stay free. You don't need an account to subscribe.

To cancel, go to Settings → [your name] → Subscriptions → Mercek on iPhone, or Google Play → Profile → Payments & subscriptions on Android, or tap Profile → Mercek Pro → Manage subscription in the app. If you cancel before the trial ends you won't be charged. If you changed phones, Restore purchases on the Pro screen moves your subscription to the new device. Refund requests are made through the store (Apple: reportaproblem.apple.com).

Do I need an account? How do I sign in with Google or Apple?

No; scanning, scores, comparison and the Pro subscription work without an account. An account backs up your saved products and links your Pro subscription to it. On Profile → Sign in or create an account you can use Continue with Apple, Continue with Google or e-mail and password. With Google and Apple, the first sign-in creates the account automatically. With Apple you can choose to hide your e-mail.

I forgot my password

Tap Forgot my password on the sign-in screen and enter your e-mail; you will receive a link to set a new password. If it doesn't arrive, check your spam folder. Accounts created with Google or Apple have no password; sign in with the same method.

How do I delete my account?

Profile → Delete account. For your security you verify your identity again (password, Google or Apple); your account, the saved-products list on our server and your sign-in record are then permanently deleted. If you have a Pro subscription, deleting your account does not stop it; cancel it separately in the App Store or Google Play.

If you can't reach the app (new phone, app removed), you can also request deletion by email: write "delete my account" to kaanerenmemisoglu@gmail.com from your account's email address. After we verify your identity, your account and its server data are deleted within 30 days; product contributions remain in anonymised form.

How is the score calculated?

Every product starts at 100 points; each penalty and bonus applied is recorded by name. Tap "How was this score calculated?" on the product screen to see the full breakdown. There are no hidden weights: the items you see add up to the score. Ingredient risk levels are based on EFSA, IARC and SCCS assessments, the annexes of the EU Cosmetics Regulation and World Health Organization recommendations, and the source of every ingredient is listed in the in-app ingredient library.

Why did a product get a low score?

If the ingredient list is missing or unreadable, a product is not declared "clean": its score ceiling is lowered, and this deduction appears as a separate line in the breakdown. Once the data is complete, the score rises by itself.

Why don't medicines get a score?

On purpose. Telling someone a medicine is "45/100 — avoid" could push them to stop a prescribed treatment; with food we choose, with medicine we treat. For the same reason no alternative medicine is suggested — choosing an equivalent medicine is for a doctor or pharmacist. For medicines we show the active substance, ATC code, marketing authorisation holder, prescription colour and the excipients extracted from the patient leaflet.

Do I have to grant camera permission?

No. If you don't, the app keeps working; use "Enter barcode manually" on the scan screen to type the number. No image is stored or sent while scanning barcodes; a photo reaches our server only when you choose to add a product and tap "send".

Where is my data stored?

Your scan history and sensitivity profile stay only on your device. If you create an account, your e-mail, saved products and subscription status are stored on our server; sign-in runs on Google's Firebase. There are no analytics or advertising tools. See the privacy policy for details.

How do I clear my history?

Use Clear history at the bottom of the History tab. Removing the app from your device also deletes everything on the device, including scan history, saved products and the sensitivity profile.

How do I turn on sensitivity warnings?

Mark topics such as lactose, gluten, palm oil and fragrance allergens in the Profile tab. When a marked ingredient appears in a product, a warning shows at the top of the product screen.

How do I change the language?

Mercek follows your device language (Turkish or English). To change it, go to Profile → Language.

Why is scanning slow or returning nothing?

Product lookups need an internet connection. If the connection is weak or a source database is temporarily not responding, results may be delayed; try again in a few seconds. The medicine lookup takes a separate route, so one failing does not affect the other.

Known limitations

• Product coverage depends on community data; gaps are more likely for local brands.
• The medicine index is based on TİTCK's weekly list; very recently licensed products may not be recognised until the next update.
• Leaflet matching can't be established for every medicine; when in doubt we deliberately don't match.
• Alternatives are shown only for products with enough data that are clearly better.

Disclaimer

Mercek is an information app; it does not provide medical advice, diagnosis or treatment. Consult your doctor or pharmacist for decisions about allergies, nutrition or medicine use. The official label on the packaging always prevails.