Your notes stay with you.

1. Who we are

Matemasie is a product of MOSOBI SARL, based in Abidjan, Côte d’Ivoire, which owns the app and the brand. It is developed and distributed on the Microsoft Store and Google Play by AFINOV SARL, a company in the same group.

Questions about your data: privacy@matemasie.app.

2. What we collect

Nothing. There’s no Matemasie account, no advertising, no analytics, no telemetry and no crash reporting, and the app never contacts a MOSOBI or AFINOV server. We don’t receive your notes, your passwords, your email address or the list of your devices.

Two exceptions, both started by you: if you buy Matemasie Plus, the store sends us the sales information it gives every publisher (section 6); if you email us, we get your message and your address (section 8).

3. Where your data lives

On your device, your notes, their attachments, their history and the vault are kept in a SQLCipher database encrypted with AES-256. Its key is protected by the operating system: Windows Data Protection (DPAPI) or the Android Keystore.

Sensitive notes and vault records get a second layer of encryption, AES-256-GCM, with a key that only opens with your passphrase, Windows Hello or your fingerprint.

If you turn on sync or cloud backup, every file is encrypted with AES-256-GCM on your device before it goes to the storage you picked: OneDrive, Google Drive, a WebDAV server, a folder, or your other devices on your local network.

Matemasie asks Google and Microsoft for the narrowest access they offer. On Google Drive, the drive.file permission: Matemasie only sees files it created itself, never the rest of your Drive. On OneDrive, the Files.ReadWrite.AppFolder permission: a single folder set aside for the app, inside the Apps folder of your OneDrive. You sign in through your browser, directly with Google or Microsoft, and the access token stays on your device, protected by the system.

4. What your storage provider sees

Encryption hides what’s in the files, not the fact that they exist. Google, Microsoft or whoever hosts your WebDAV server can see:

• a folder called Matemasie and how it’s organized;
• how many files there are, how big they are and when they were written;
• how many devices you have, since each one writes to its own subfolder under a random ID;
• the IP address of the device connecting, and the account the storage belongs to.

They can’t see the text of your notes, their titles, their tags or anything in your vault.

5. Optional services

Each one only runs if you turn it on. As with any connection, the server on the other end sees your device’s IP address.

• Password breach check (the Pwned Passwords service from Have I Been Pwned, api.pwnedpasswords.com), only after you explicitly agree. Matemasie sends the first 5 characters of a password’s SHA-1 hash, never the password or its full hash. The service answers with every hash that starts the same way, padded so its size gives nothing away, and the comparison happens on your device.
• Community language catalog, off by default. When it’s on, it downloads the list of languages and the ones you install (from raw.githubusercontent.com by default, and you can change the address), using plain read requests that carry none of your data.
• Local network sync. Your devices announce themselves on the local network (mDNS) under a random name, then exchange encrypted files over a TLS connection, only between paired devices and only from local network addresses.

Remote desktop and SSH connections are made by Windows’ own tools (mstsc and ssh). Matemasie only launches them.

6. Purchases

Subscriptions and the lifetime license are sold only through Google Play or the Microsoft Store. The store handles the payment, your payment method and your account, under its own privacy policy. It sends AFINOV SARL the sales information it gives every publisher (product, date, country, amount, order number), which we use for accounting, legal obligations and answering your support requests.

To unlock Plus on your other devices without a server, the device you buy on saves a signed receipt in your vault, encrypted like your notes. On Android, Google’s billing library ships without its logging module, so it sends no statistics from Matemasie.

7. Google user data

Matemasie uses Google APIs for one purpose: to write and read the encrypted files of your sync and backups in your Google Drive, and to show you which account is connected. That information stays on your device. It is never sent to MOSOBI or AFINOV, sold, used for advertising, or read by a person.

Matemasie’s use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.

8. Retention and deletion

Your data stays on your devices and in your storage for as long as you keep it. We hold no copy, so you’re the only one who can delete it. To erase everything:

1. uninstall Matemasie from each device;
2. delete the Matemasie folder from your Google Drive, OneDrive or WebDAV server, along with any backups and exports you saved elsewhere;
3. remove Matemasie’s access in the security settings of your Google or Microsoft account.

Emails you send to privacy@matemasie.app or support@matemasie.app are kept as long as it takes to deal with your request. Sales information from the stores is kept for as long as our accounting obligations require.

9. What protection can’t do

• Malware running under your account while your notes are open sees what you see, what you type and what you copy. No notes app can protect you from that.
• So that search works while the vault is locked, a few details of each record (title, type, tags, username, website domain, last 4 digits of a card, Wi-Fi network name) are protected only by the database encryption. You can hide them record by record.
• If you lose both your passphrase and your recovery key, nobody can open your sensitive notes or your vault again, including us.
• A device removed from your vault only wipes its data if it reconnects. On an SSD or a phone, physically erasing files isn’t guaranteed.

10. Children, your rights, changes

Matemasie isn’t aimed at children and collects no data about them, or about anyone else.

The little data we do receive (sales information, emails) is handled under Ivorian law no. 2013-450 of June 19, 2013 on the protection of personal data, and under the law of your country where it gives you more protection. You can ask to see it, correct it or delete it, or object to how it’s used, by writing to privacy@matemasie.app. In Côte d’Ivoire, you can also contact ARTCI, the data protection authority.

If this policy changes, the new version is posted on this page with its date.

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