Lunalog

Privacy Policy

Last updated: November 4, 2026

Lunalog is a calorie and nutrition tracking app for iPhone. This policy explains what personal data Lunalog collects, why, who helps us process it, how long we keep it, and the choices you have. If anything is unclear, write to support@lunalogapp.com or use Profile › Support in the app.

The short version

Who is responsible for your data

Lunalog is developed and run by an independent developer in the Czech Republic, who is the controller of your personal data under the EU General Data Protection Regulation (GDPR) and is named as the seller on Lunalog’s App Store page. In this policy, “we”, “us” and “our” mean Lunalog’s developer.

You can contact us about privacy at any time at support@lunalogapp.com or in the app under Profile › Support.

Lunalog is a small independent project and hasn’t appointed a data protection officer. Your message goes straight to the developer.

The data we collect

We collect data you give us, data created as you use Lunalog, and data from services you choose to connect: Apple or Google for sign-in, Apple Health, and the App Store for subscriptions. Lunalog can’t work without an account and the information you log.

Account details. Lunalog has no passwords. You sign in with Apple, with Google, or with a one-time code we email to you. Apple and Google share your name, your email address (with Sign in with Apple this can be a private relay address) and an account identifier with us. With email sign-in we receive only your email address. We keep basic account records, such as when you created your account and last signed in or used the app, and technical details of your sign-in sessions, such as IP address and device type, to keep your account secure.

Profile and body information. During setup and in Profile › Personal info you can give us your date of birth, sex or gender, height and weight, your goal (lose, maintain or gain weight), goal weight, weekly pace, daily calorie budget and macro targets, and preferences such as units and time format. Other setup answers, such as how you heard about Lunalog, your diet style, how often you work out or your biggest obstacle, are only used on your device to tailor setup and your starting plan, and aren’t saved to your account.

Food logs. The meals and ingredients you log (names, descriptions, times, portions, calories and nutrients), the text or dictation you used to describe them, details of AI estimates (such as an estimate’s reasoning and confidence), your saved meals and foods, and your daily and monthly summaries.

Photos. Meal photos, progress photos (photos of your body that you take to track changes) with their captions and albums, and photos you attach to chats or support messages. Progress photos can be especially sensitive. They’re stored privately and are never sent to our AI provider unless you attach one to a chat yourself.

Weight and progress. Weight entries you log or import, your body plans and their history, and values we calculate from your data, such as your estimated maintenance calories.

Apple Health. If you turn it on, Lunalog reads your body weight measurements (value, date and time) and no other health data, and can add the nutrition of the meals you log to Apple Health. See “Apple Health” below.

Voice. When you dictate a meal or a message, or talk to Luna in voice mode, your phone’s own speech recognition turns what you say into text on the device. The audio is never sent to us or to any provider, and the temporary recording on your device is deleted.

Chats with Luna. Your messages, Luna’s replies, photos and meals you attach, reactions, chat titles, and any custom instructions or notes you give Luna. Chats sync so you can continue on another device.

Drawings and streaks. Your Drawings collection, streak days, gems, chests and related preferences.

Subscription information. Whether you have Lunalog Pro, which plan you’re on, trial or introductory offer status, renewal and expiry dates, and purchase events. Payments are handled entirely by Apple. We never see your payment card details.

Support conversations. When you contact us in Profile › Support, we receive the topic and subject you choose, your messages, photos you attach, and technical details that help us troubleshoot: app version, iOS version, device model, time zone and region setting. When you email support@lunalogapp.com, we receive your email address and name as your email app sends them, the subject, your message and up to four attached images.

Notification token. If you turn on notifications for support replies, your iPhone’s push notification token (an identifier Apple gives Lunalog on that device) is stored with your account, so we can tell you when we’ve answered.

In-app messages. We sometimes show messages in the app, such as news, a required update or a gift. We record when you’ve seen a message so we don’t show it again.

Usage analytics. The app sends our analytics provider, PostHog, events about how you use Lunalog: for example when the app is opened, how long a session lasts, which screens and onboarding pages you view, when you see the paywall or subscribe, and when features such as meal logging, the camera, dictation, chat or voice mode are used. Events carry technical details about the app and your iPhone (app version, iOS version, device model, screen size, language, time zone and whether you’re on Wi-Fi or cellular), and some carry details like which AI model was used, the number of tokens and images, or an error code. Of your onboarding answers, only where you heard about Lunalog and whether you’ve used other apps are sent. Before you have an account, events carry a random ID made on your iPhone; when you sign in, they’re linked to your random account ID. Events never include your name, email, meals, photos, messages or health values.

Security and technical data. To protect Lunalog and keep AI costs fair, our servers keep limited technical records: a keyed, one-way hash of your IP address (never the address itself) for rate limits, and AI usage metadata (the feature, model, number of tokens, images or characters of speech, the result status and the time), but never your prompts, photos or Luna’s replies. Our hosting providers also keep short-lived server logs, which can include IP addresses.

What we don’t collect. We don’t collect your precise location, contacts, browsing history or advertising identifiers (such as Apple’s IDFA), and Lunalog contains no advertising or cross-app tracking tools. If a photo you choose contains location information from your camera, we don’t read or use it.

What stays on your device

How we use your data and why

The GDPR requires a legal basis for each purpose, which we list too.

We don’t use your data for advertising or marketing, and we don’t sell it. We don’t make decisions about you based solely on automated processing that have legal or similarly significant effects on you. Your calorie budget and AI estimates are suggestions that you can always change.

Your consent for health data

Your diet, weight, body measurements and body photos can reveal information about your health, so the GDPR treats them as a special category of personal data. When you create your account, the sign-in screen asks you to agree to this policy, including that Lunalog keeps this data to provide Lunalog. Continuing gives your explicit consent. Lunalog can’t store or sync your logs without it. Sending data to our AI providers for AI features needs a separate consent, which the app asks for before your first AI request (see “AI features”).

You can withdraw this consent at any time by deleting your account (see “How to delete your account and data”). You can also delete individual entries, photos or chats whenever you want. Withdrawing consent doesn’t affect processing that took place before.

AI features

Who processes the data. Our AI features are powered by Anthropic, PBC (USA). In voice mode, Luna’s spoken replies are created by Inworld (Theai, Inc., USA). Both process the data as our service providers under data processing agreements. We may change providers to keep Lunalog accurate and affordable, and will update this policy when we do. Your phone never sends data to them directly: requests go to our backend, which checks your subscription and usage limits and forwards each request to one provider using our account.

Your consent. Before Lunalog sends anything to our AI providers, the app shows what is sent and asks for your permission. Your answer is stored with your account and applies on all your devices. If you choose Not now, nothing is sent and you can still log meals by hand. To withdraw it, email support@lunalogapp.com from your account’s address or write to us in Profile › Support. We turn AI features off for your account, and the app asks for your permission again before any new AI request.

What we send, and when.

What we don’t send. Luna never sends your name, email address, date of birth, sex or gender, or height. Progress photos are never sent unless you attach one to a chat yourself. With text and photo requests we include a one-way hash of your random Lunalog account ID, never your name or email, so the provider can help detect misuse of its service.

How our AI providers handle your data. Neither provider uses data sent through its API to train its models. Each may keep requests and responses for a limited time to provide the service and detect abuse before deleting them; for Anthropic that is up to 30 days. Anthropic may keep a request its safety systems flag as misuse for up to 2 years, and either provider keeps data longer when the law requires it.

What we keep. Our AI logs contain only the usage metadata described above, never your prompts, photos or Luna’s replies. The results, such as a meal’s estimated nutrition or Luna’s reply, are saved to your account like the rest of your logs.

Accuracy. AI makes mistakes. Nutrition estimates can be wrong, and Luna is an AI, not a person and not a health professional. Please see our Terms of Use. If Luna says something offensive, harmful or wrong, email support@lunalogapp.com. A person reviews every report.

Apple Health

Lunalog can import body weight from Apple Health and add your meals’ nutrition to it. Both are optional and stay off until you turn them on.

Who can see your data

Lunalog has no social features, so other users can’t see your data.

On our side, people only access your data when needed: to help with a request you made, to investigate a security problem or misuse, or when the law requires it. Support requests are handled in Lunalog’s internal support tool by the developer and anyone who helps with support, who are bound to confidentiality. The tool shows support conversations and the photos sent with them, the name and email address on your account, whether you have Lunalog Pro, when your account was created and last used, and the technical details sent with a request. It doesn’t show your meals, photos, weights, body details or chats. Support staff can add internal notes to a request and can stop someone from contacting Support if they abuse it. Only if you’ve turned on Luna AI, the support tool can ask Anthropic to help draft a reply, sending your request’s messages, our internal notes and your subscription status, never your name, email address or device details. Requests sent by email never go to Anthropic. A person reads and sends every reply.

Every action in the support tool, including opening your request or looking up your account, is recorded in an access log that only the developer can read. The log is deleted after 1 year.

Who we share data with

We don’t sell or rent your personal data, and we don’t share it with advertisers or data brokers. We share it only with the service providers that help us run Lunalog, and with Apple and Google as described below.

Our service providers process your data only on our instructions, under data processing agreements that require them to protect it at least as well as this policy does:

Apple and Google also process data as independent controllers, under their own privacy policies:

We may also disclose data when the law requires it (for example, a valid court order), to protect the safety, rights or property of our users, us or others, or if Lunalog is transferred to a new owner, in which case this policy continues to apply to your data and we’ll tell you in advance.

International data transfers

The service providers above are based in, or store data in, the United States, outside the European Economic Area. We transfer data there only with the safeguards the GDPR requires: the European Commission’s adequacy decision for the EU–U.S. Data Privacy Framework, for providers certified under it, and otherwise the European Commission’s Standard Contractual Clauses in our providers’ data processing agreements.

We add further protections: encryption in transit and at rest, private storage with strict access control, and a random account ID instead of your name or email when we send data to our AI, analytics and subscription providers. You can ask us for more information or a copy of the safeguards.

How long we keep your data

How we protect your data

Lunalog isn’t end-to-end encrypted, and no system is perfectly secure. If a personal data breach is likely to put your rights at risk, we’ll notify the data protection authority within 72 hours and tell you without undue delay where the law requires it. Exports you save from Lunalog aren’t encrypted, so keep them somewhere safe.

Your rights

Under the GDPR you have the following rights. You can use most of them directly in the app:

For anything you can’t do in the app, contact us via Profile › Support or support@lunalogapp.com. It’s free, and we’ll respond within one month; if a request is complex we may extend this by up to two more months and will tell you why. We may need to confirm it’s really you first, for example by asking you to write from the signed-in app or from the email address linked to your account.

How to delete your account and data

You can delete your Lunalog account and the data linked to it at any time, free of charge.

In the app

  1. Open Lunalog and go to Profile › Data controls.
  2. Tap Delete account and confirm.
  3. Confirm your identity when asked: with Apple or Google if you use one, otherwise with a code we email you.

Deletion starts immediately and usually finishes within a few hours.

By email

Email support@lunalogapp.com from the email address linked to your Lunalog account, with the subject “Delete my Lunalog account”. If you signed in with Apple and chose to hide your email, include the relay address Apple created for Lunalog (you’ll find it in your Apple Account settings under Sign in with Apple). We’ll confirm the request by writing to the address linked to your account and complete the deletion within 30 days.

What we delete

What we keep, and for how long

Important: deleting your account doesn’t cancel your subscription. Cancel it in your App Store subscription settings first, or you may continue to be charged. If you used Lunalog on other devices, delete the app there to remove its local copy.

Children

Lunalog is for adults aged 18 and over. We don’t knowingly collect personal data from anyone under 18. If you believe someone under 18 has given us personal data, contact us and we’ll delete it.

Permissions and your choices

Lunalog asks for iPhone permissions only when you use a feature that needs them. You can change them at any time in Settings:

We don’t send marketing emails or marketing notifications.

This website

lunalogapp.com doesn’t use cookies, analytics or tracking. Cloudflare, which hosts it, processes your IP address to deliver the pages and protect the site.

Changes to this policy

We’ll update this policy when Lunalog or the law changes, and the date at the top shows when it last changed. If we make significant changes, we’ll tell you in the app before they take effect and, where a change needs your consent, ask for it again.

Contact

Email support@lunalogapp.com, or use Profile › Support in the app.