Privacy policy

Last updated October 23, 2026

Marginalia is made by Gleb Matsko, an independent developer in Serbia working as glebthebread (“we”), who is responsible for your data under this policy. This policy explains what the app keeps on your iPhone, what leaves it, and what you can do about it. Questions go to marginalia@glebthebread.com.

The short version

• There are no accounts. We never ask for your name or email.
• Your answers, notes and decisions stay on your iPhone. We never receive them.
• The app sends anonymous usage statistics to Google Analytics for Firebase, and subscription records to RevenueCat.
• No ads, no tracking across other apps or websites, and we sell nothing about you.
• Settings › Erase all data deletes everything from your iPhone and resets the analytics identifier.

What stays on your iPhone

Your answers to each day's question, your evening notes, the decisions you work through, your reminder times and your settings. They are stored in the app's own storage on your device and shared only with the Marginalia widget on the same device. They are included in your device backups, such as iCloud Backup, if you use them; Apple handles those backups under its own privacy policy.

Pictures you share from the app are made on your iPhone and go only where you choose to send them.

What leaves your iPhone

Usage statistics (Google Analytics for Firebase)

To learn which parts of the app help people and which don't, the app records a few events:

• moving through the first-launch steps;
• answering the day's question (not which question or which answer);
• writing an evening note (not what you wrote);
• opening a thinking method (which one, not what you typed);
• seeing the membership screen, and from where.

Firebase also collects some information on its own: a random app instance identifier, device model, iOS version, app version, language, session times, first launch, in-app purchase events, and an approximate location (country or region) derived from your IP address. The app does not use the advertising identifier (IDFA) and does not link this data to your identity. Google processes it for us as a service provider; see Firebase privacy and security.

Subscriptions (RevenueCat and Apple)

Apple handles all payments. We never see your card or your Apple Account details. To know whether you are a member, the app uses RevenueCat, which receives an anonymous random identifier, your purchase and subscription history, your App Store country, and the device and app version. See the RevenueCat privacy policy.

Siri, widgets and notifications

Reminders are scheduled on your iPhone, not sent from a server. Widgets run on your iPhone. When you talk to Siri, Apple processes your request under Apple's privacy policy; Marginalia only receives the answer you chose.

Email

If you write to us, we use your address and message to answer you, and keep them only as long as that takes.

Why we use this data

Usage statistics help us improve the app, which is our legitimate interest. Subscription records are needed to provide the membership you bought. Nothing is used for advertising or profiling.

How long it is kept

• On your iPhone: until you erase it in Settings or delete the app.
• Usage statistics: deleted automatically under the data retention setting of our Google Analytics project.
• Subscription records: as long as needed to provide your membership and meet legal and tax obligations.

Your choices and rights

• Erase all data. In the app, open Settings and tap Erase all data. Your answers, notes and decisions are deleted from your iPhone, reminders are cancelled, and the analytics identifier is reset, so later statistics can't be tied to earlier ones. Your membership stays with your Apple Account.
• Delete the app. This deletes everything the app stored on your iPhone.
• Notifications. Turn reminders off in the app or in iOS Settings at any time.

Under Serbia's Law on Personal Data Protection, the EU and UK GDPR and similar laws, you may have the right to access, correct, delete or object to the processing of your personal data. You can also complain to Serbia's Commissioner for Information of Public Importance and Personal Data Protection, or to the data protection authority where you live. Write to us and we'll help. Because we don't know who you are, we usually can't find your statistics without the app instance identifier; erasing your data in the app is the quickest way to cut the link.

Where data is processed

Google and RevenueCat may process data in the United States and other countries, under their own safeguards for international transfers.

Children

Marginalia is not directed at children under 13, and we don't knowingly collect personal data from them.

Changes

If this policy changes, we'll update it here and change the date at the top. Significant changes will also be noted in the app's release notes.