Privacy Policy

Last updated: August 8, 2026

Lumi (“we”, “us”) is an AI calorie deficit tracker operated by Furkan Hatipoglu. This policy explains what information we collect, how we use it, and the choices you have.

1. Information we collect

Account

When you use Lumi we may create or use a Firebase Authentication account (including anonymous or signed-in identifiers) so features like AI meal analysis quotas and sync-related services work securely.

Profile and goals

Information you provide such as height, weight, age-related inputs, sex, activity level, calorie or protein targets, measurement preferences, and fasting rhythm settings.

Meals, weight, and journal data

Meal logs, food items, macros, notes, weight entries, and related timestamps you save in the app. Much of this stays on your device (SwiftData). Some requests are sent to our servers when you use AI features.

Photos and text for AI meal analysis

If you scan a meal by photo and/or text, that content is sent to our cloud function and processed by our AI provider (OpenAI) to estimate nutrition. Do not submit images of other people without permission, or any content you do not want processed for estimation.

Apple Health (HealthKit)

If you grant permission, we may read health and activity data you allow (for example steps, active energy, and related metrics) to improve energy-balance estimates. We do not write HealthKit data unless the product explicitly offers that and you consent. You can revoke Health access in iOS Settings at any time.

Purchases and subscriptions

Subscription status is handled through Apple In-App Purchase and our subscription partner (RevenueCat). We receive entitlement information needed to unlock Premium features—not your full payment card details.

Analytics and diagnostics

We use Firebase Analytics (and related Firebase services) for product usage, funnels, and stability. This may include device and app version information and event names (for example onboarding or paywall views). We use this to improve Lumi, not to sell personal profiles.

2. How we use information

3. AI processing

Meal photos and descriptions you submit for analysis are transmitted to our backend and to OpenAI to generate structured nutrition estimates. Estimates are approximate and for personal wellness tracking only— not medical advice. We configure the service for this product purpose and apply rate limits to protect the service.

4. Where data lives

Providers may process data in the United States or other countries. By using Lumi you understand that your information may be transferred to those locations with appropriate safeguards offered by those providers.

5. Sharing

We do not sell your personal information. We share data only with service providers who help us operate Lumi (listed above), when required by law, or with your direction (for example when you contact support).

6. Retention

Device data remains until you delete it or remove the app (subject to device backups you control). Server-side auth and usage records are kept as long as needed to provide the service and prevent abuse. You may request deletion of account-related server data by contacting us (see below).

7. Your choices and rights

Depending on where you live, you may have additional rights under local privacy laws. Contact us and we will help where we can.

8. Children

Lumi is not directed at children under 13 (or the minimum age required in your country). We do not knowingly collect personal information from children.

9. Security

We use industry-standard protections such as encrypted transport (HTTPS) and authenticated API access. No method of transmission or storage is 100% secure.

10. Changes

We may update this policy from time to time. We will revise the “Last updated” date above. Continued use of Lumi after changes means you accept the updated policy.

11. Contact

Questions about privacy:

Lumi — operated by Furkan Hatipoglu