MacroStack AI ("the App") is a nutrition tracking app for iPhone and iPad. This policy explains what information the App accesses, how it is used, and how your data is protected. We take privacy seriously and collect only what is strictly necessary to provide the app's features.
We do not sell your personal data, and we never will. We have no advertising partners, no analytics providers, and no data brokers. Our only revenue is your payments.
Looking for the Android privacy policy? View it here. Need help? Visit support.
1. Data Storage On-device, plus your own iCloud if you choose
Your nutrition logs, food entries, weight records, profile information, and goals are stored locally on your device using Apple's on-device database (SwiftData). This log data is never uploaded to any account we hold, and we do not maintain any database that stores your personal health or nutrition data. The AI coach and food scanner route limited data through our proxy server to generate replies. Exactly what is sent is listed in Section 5.
The home-screen and lock-screen widgets read a small snapshot of today's totals (calories, macros, streak) from a shared on-device App Group container. This snapshot also stays on your device and is never transmitted.
Automatic backups. The App keeps a backup file of its own data on your device, refreshed at most once an hour, in a folder you can see in the Files app under On My iPhone → MacroStack. It stays on the device and is included in your iPhone backups like the rest of the App's data. You can turn this off in Settings → Backup, which stops new backups. Delete Backups in the same place removes the ones already saved.
iCloud Drive backup (optional, off by default). If you turn on Settings → Backup → iCloud Drive, the App keeps a copy of that backup file in your own iCloud Drive, in a MacroStack folder under Files → iCloud Drive. That copy lives in your Apple account, is encrypted by Apple in transit and at rest, and is readable only by you and by MacroStack on devices signed into your account. We have no access to it and no servers are involved: it is a file in your storage, the same as one you would save there yourself. It exists so your data survives deleting the App or moving to a new iPhone. Weigh-ins that came into MacroStack from Apple Health are left out of the iCloud copy, in keeping with Apple's HealthKit rules. Turning the setting off stops new copies. Settings → Backup → Delete Backups removes the MacroStack folder from your iCloud Drive, and you can also delete it yourself in Files at any time.
iCloud Sync (optional, off by default). If you turn on Settings → Backup → iCloud Sync, the App keeps your food log, weigh-ins, goals, check-in history, and saved coach messages in your own private iCloud database, so your other iPhones and iPads signed into the same Apple Account show the same data. Apple stores it under your account; we have no access to it and cannot read it. Weigh-ins that came in from Apple Health never go to iCloud, by Apple's rules: each device brings its own in from Health. Turning sync off stops it; the data already in your iCloud stays there under your control (iOS Settings → your name → iCloud → Manage Storage).
2. Camera & Photo Library Access
The App uses your camera to scan food and barcodes for nutrition tracking. You may also select photos from your photo library for AI-powered food analysis. When you use the AI Food Scanner, your food photo is sent through our proxy server to Google's Gemini API for analysis. We use the paid Gemini API tier, which means Google does not use your photo or the returned analysis to train or improve its products, and does not route them to human reviewers. Google retains the request only for a limited window to detect abuse of its service and to meet legal requirements. The App itself never stores your food photos on our servers. No photos are shared with any third party beyond Google for the single purpose of this analysis.
3. Location Access
The App requests location access solely to help you find nearby restaurants in the Coach feature. Your location is handed to Apple's on-device MapKit framework, which performs the search via Apple's Maps service; no third-party mapping provider is used. No health, nutrition, or fitness data is ever combined with or sent alongside your location. You can deny or revoke location access at any time in your device settings.
4. Apple Health (HealthKit)
Apple Health sync is off by default. If you turn it on in Settings → Privacy and grant permission, the App exchanges these kinds of data with Apple Health on your device:
- Written to Health: your body weight whenever you log, edit, or delete a weigh-in, and each day's total calories, protein, carbohydrates, and fat after any logging change. An edit replaces the earlier entry rather than adding to it.
- Read from Health: body weight entries that other apps or devices (for example a smart scale) add to Health, so they appear in your weight history and inform your calorie goal. The App reads no other Health category.
Health data stays on your device, stored by Apple. It is never sent to our servers, never used for advertising or marketing, and never shared with anyone. Turning sync off stops all reading and writing and leaves what is already in Health untouched. You can also revoke access at any time in iOS Settings → Privacy & Security → Health → MacroStack AI. Weigh-ins read from Health are never placed in the optional iCloud Drive backup.
5. AI Features
The App uses cloud-based AI (Google Gemini) to power the nutrition coach and food scanner. When you use these features, your messages and food photos are sent to our proxy server, which forwards them to Google's Gemini API for processing. The data sent includes:
- Your coach messages and questions, including recent turns of the current conversation so the coach can follow the thread
- Your daily calorie and macro context (goal, consumed, remaining)
- When you chat with the coach and Share Log Context is on (Settings > Privacy, on by default): today's logged foods (names, meal slots, portions, calories and macros), the current local time of day (hour only), your fasting eating window and whether it is currently open if you use fasting, and app-computed progress data (average calorie intake, estimated daily burn from your logs, weight trend, and recent goal adjustments). Turning the toggle off keeps all of this out of coach requests, and weekly recaps are then generated on-device instead.
- Saved dietary preferences, if you ask the coach to remember any
- A short list of candidate foods from the app's bundled database, used to keep suggestions grounded
- When you ask for a weekly recap: your last 7 days' averages (calories and macros), days logged, adherence to your goal, logging streak, and your weight change for that week if you logged weigh-ins
- Food photos (for the AI scanner only)
- A food name you typed while logging, if you tap Estimate Macros with AI when the food isn't in the on-device database
No personal identifiers (name, email, account info) are included in AI requests. A randomly generated device identifier is used by our proxy solely for rate limiting and is not forwarded to Google.
We use the paid Gemini API tier. Under Google's paid tier terms, Google does not use your prompts or responses to train or improve its products, and does not route them to human reviewers. Google retains requests only for a limited window to detect abuse of its service and for legal compliance. Google's full handling of this data is governed by the Gemini API Terms of Service.
6. Food Database
The App includes a bundled food database stored on your device for nutrition lookups. For barcode scans, the App may also query the public Open Food Facts API over the internet to retrieve nutrition information when an item isn't in the bundled database. In those cases, only the scanned barcode is sent. No personal data, account information, or device identifiers are included in these requests.
The bundled food database is built from Open Food Facts data, © Open Food Facts contributors, available under the Open Database License, and from USDA FoodData Central, which is in the public domain.
7. Rate Limiting
To ensure fair usage, the App generates a random device identifier (UUID) on first launch. This identifier is used only to enforce daily usage limits on AI features. It is not linked to your identity, Apple ID, or any personal information. The identifier is stored on your device and on our rate-limiting server. No usage data, message content, or personal information is stored alongside it.
8. Data Export
The App allows you to export your data as a backup file, with optional password-based encryption. Exported files are created temporarily on your device and shared only through the method you choose (e.g., AirDrop, Files). We never receive or have access to your exported data.
9. Notifications
If you grant notification permission, the App schedules local reminders on your device, such as meal prompts, streak-save alerts, and weigh-in reminders. These are scheduled and delivered entirely by iOS on-device. The App does not use push notifications, and no notification content is ever transmitted to our servers.
10. Analytics & Crash Reporting
The App does not collect analytics, advertising data, or crash reports. No usage data is transmitted. (Apple may offer to share anonymized device-level diagnostic data with developers through its own Share With App Developers setting; this is a system feature you can toggle in Settings → Privacy & Security → Analytics & Improvements.)
11. Children's Privacy
The App is not directed at children under 13. We do not knowingly collect any information from children.
12. Changes to This Policy
We may update this policy from time to time. Any changes will be reflected on this page with an updated date. Continued use of the App after changes constitutes acceptance of the updated policy.
13. Contact
If you have any questions about this privacy policy, please contact us at: rexhep.rexhepi.5@gmail.com