LumaSync Privacy Policy

Effective 26 September 2026.

In short

Data about your cycle and health is stored on your phone, encrypted. It goes to Apple Health or Health Connect only if you turn that connection on yourself, and to our server only if you create an optional account with a cloud backup yourself or use it to share your cycle with someone close, and then only encrypted with a key we do not know. We cannot access it and we cannot share it with anyone. Without an account you give us nothing, and you create an account with Apple or Google without us learning your name, email or phone number. We show no ads, we do not sell data and we use no third party advertising or analytics tools. The app is not a medical device and not a method of contraception.

Who publishes the app

LumaSync is published by Axperts Dariusz Zalewski, ul. Pelikana 1/3, 71-698 Szczecin, Poland, tax ID (NIP) 851 319 2109, email biuro@axperts.pl.

The data you enter in the app is kept by you, on your phone. If you create an account, we are the controller of the account data and of the encrypted backup on our server, even though we cannot read the backup. Otherwise we are the controller only of the technical data described in the section about connections to our server.

Data on your phone

Your phone keeps: period dates and flow, symptoms, mood, notes, information about sexual activity, tests and contraception, measurements, the mode you chose (for example pregnancy with the date of your last period) and settings. They are encrypted with a key created on your phone that never leaves it. A phone backup cannot restore them on another device, so use the export in the app or the optional account with a cloud backup to move your data. Calculations and reminders run on the phone itself.

Apple Health and Health Connect

The connection stays off until you turn it on yourself in the You tab. Once it is on, LumaSync saves your period, spotting, test results, cervical mucus, sexual activity, temperature and weight to Apple Health (iPhone) or Health Connect (Android), and in Apple Health also your symptoms, and brings in the same data saved by other apps from the last two years. Notes and your own tags stay only in LumaSync. Data in Apple Health and Health Connect is governed by Apple's and Google's rules: Apple Health can sync it through iCloud if you have that turned on in Health settings, and Health Connect keeps it on your phone. This data never reaches our servers. When you turn the connection off, you can delete everything LumaSync saved there, and deleting all data in LumaSync deletes it automatically.

Account and cloud backup

The account is optional and free, and the app works fully without it. You create it in the You tab, under Account and backup, by signing in with Apple or Google, under their terms. Apple or Google then gives us an identifier of your account with them, and we store only a hash of it, which cannot be turned back into the identifier. We do not store your name or email. When you sign in with Apple, we also keep an encrypted Apple token, only so that we can disconnect LumaSync from your Apple account when you delete your account.

The backup is your entries and the settings shared between phones, encrypted on your phone (AES-256-GCM) with a key created on your phone. The key reaches only your own devices: through iCloud Keychain on iPhone, through Google's backup on Android or through a recovery code you write down yourself. On the server we keep the encrypted documents, their size, version numbers and save times, the date the account was created, a check value of the key (which cannot be turned back into the key) and, for each signed in phone, a hash of the session token, the type of system and the time it was last used. App lock and the connection to Apple Health or Health Connect stay separate on each phone.

The legal basis for the account data is the agreement to use the account (Article 6(1)(b) GDPR), and for keeping the encrypted backup, which contains health data, your explicit consent given when you sign in (Article 9(2)(a) GDPR). You withdraw your consent by deleting the account.

You can delete the account and backup at any time in the You tab, Account and backup, Delete account and backup, or without the app at api.axperts.pl/lumasync/usun-konto. We then immediately delete the account, its sessions and all encrypted documents, and the data on your phones stays. An account that no phone has used for 13 months is deleted in the same way. If you lose all your phones and your recovery code, we cannot restore the backup, because we do not know the key.

Sharing your cycle with someone close

With an account, you can share your cycle with someone close in the You tab. They will see your cycle day, phase and period prediction (in pregnancy mode, the week of pregnancy), and if you turn it on, also today's mood, symptoms and the name you sign with. They will not see your log, notes or history. Your phone encrypts this information (AES-256-GCM) with a key created on your phone, which reaches the other person only inside the invitation link, in the part of the address our server never receives. On the server we keep the encrypted share with its version number and save time, a hash of the single use invitation token with its expiry (48 hours, deleted on acceptance) and, once the invitation is accepted, a hash of the other person's reading token, the date of acceptance and the hour they last viewed it. The other person does not create an account and gives us no data about themselves.

The legal basis for passing on this information is your explicit consent given when you send the invitation (Article 9(2)(a) GDPR). We process the other person's token and viewing time to show them the share and to show you its status (Article 6(1)(b) GDPR). You withdraw your consent by ending the sharing in the You tab: we then immediately delete the share and the tokens, and the last downloaded view disappears from the other person's phone the next time it connects to our server. The other person can also disconnect themselves. Deleting your account deletes the share with it.

Connections to our server

Without an account, the app connects to our server api.axperts.pl in Poland only when you open an educational article, and then it sends no identifier and no calendar data, or when you accept an invitation from someone close and view their cycle, and then it sends only the reading token from the invitation. With an account, it also connects to sign in, to sync the backup and to share your cycle with someone close, as described above. The server does not store IP addresses in its request log. An IP address is written only to the error log when a request fails, and it is deleted from there after 14 days. The legal basis is our legitimate interest in protecting the service from abuse (Article 6(1)(f) GDPR). Traffic passes through the Cloudflare network, which processes the IP address on our behalf to deliver the response.

Notifications

Reminders are scheduled by the phone itself; we send no notifications from a server. By default notifications are discreet: your lock screen only shows “You have a new reminder”. You can change this in the app settings.

Your rights

You can export all your data to a file or delete it from your phone in the app settings at any time. In the Insights tab you can also create a PDF report for your doctor (cycles, symptoms and signals from the past year, without notes): it is created on your phone and reaches someone only when you send it yourself. You can delete the account and backup yourself in the app. For the account data and the technical data, you have the right of access, rectification, erasure, restriction of processing, portability and objection; write to biuro@axperts.pl. You also have the right to lodge a complaint with the Polish data protection authority (Prezes Urzędu Ochrony Danych Osobowych, ul. Stawki 2, 00-193 Warsaw).

Age

The app is intended for people aged 18 and over.

Changes

We will tell you about important changes in the app and at axperts.pl/legal/lumasync before they take effect.