Pistonbook privacy policy

Android app "Pistonbook" (ID fr.debirumans.pistonbook). In force since 22 October 2026. This page is a translation, the French version prevails.

1. Who is responsible

Pistonbook is developed by D3B1RUM4N, an independent developer in France, with no company and no investors.

Contact: contact@debirumans.fr

2. Data that stays on your phone

Everything you enter or scan in Pistonbook is stored only on your phone:

• your vehicles, their technical sheet and their photos,
• mileage readings, servicing, reminders, tyres,
• fill-ups, charges, costs, income and insurance policies,
• scanned invoices and documents, including those in the glovebox (licence, registration, insurance and so on).

The database is encrypted (SQLCipher) and files are encrypted separately (AES-256), with keys kept in the phone's secure storage. The developer has no access to them.

When a French registration certificate is scanned, the holder's name is never stored.

3. What leaves the phone, and when

The app contacts only one service: the Pistonbook server (pistonbook.debirumans.fr, hosted in France by the developer). It queries the public databases of ADEME and the European Environment Agency itself, keeping a copy of them, and the public AutoBase catalogue (autobase.maxaleau.fr) to find a vehicle's version: AutoBase only receives the D.2, D.2.1 and K codes, never your IP address.

Completing a vehicle sheet or entering a make (only when you choose to): the make, the model, the vehicle type and the version codes from the registration certificate (fields D.2, D.2.1 and K) are sent to the server. They identify a vehicle model, not a person. Only AutoBase's answer is kept in memory for at most 7 days, with no link to you, so it is not requested again.

Checking for updates: at launch, at most twice a day, the app asks the server for the latest available version. The request contains nothing else, neither an identifier nor the installed version.

Account (optional, from version 0.4.0): see section 7.

Log of a failed OBD2 adapter attempt (only if you tap "Send the log to help us", then "Send"): the app version, the adapter's name, the vehicle's protocol, the error message shown and the exchanges with the adapter. The log is anonymised on the phone before sending: no serial number (VIN), no Bluetooth address, no list of nearby devices. The server also removes any Bluetooth address or VIN that might remain. It is kept with no link to an account or IP address, read only by the developer, and automatically erased after 90 days.

The following are never sent: the number plate, the serial number (VIN), your name, your address, your documents or your photos.

The Pistonbook server logs no requests. Your IP address, sent as with any Internet access, is only used, in memory and for one minute, to limit the number of requests.

Reading documents (OCR): the text of registration certificates and invoices is read on the phone by ML Kit, a Google component. Images do not leave the phone. Google may however receive technical statistics about how this component works (performance, errors, phone model), under its own terms.

What you choose to share: an export, a PDF service history, a backup file or a report email go wherever you send them, with the app you choose. The backup file is encrypted with your password.

4. What Pistonbook does not do

• No required account: the app and the online backup work without an account, with a code only you hold.
• No ad network, no third-party analytics tool, no trackers. The website only counts page views, page by page and day by day, without cookies, without scripts and without keeping IP addresses.
• No crash report sent automatically.
• No sale, rental or transfer of data to partners.

5. Online backup (optional)

Offered to everyone during the beta, then reserved for the Premium plan (free for life for accounts created during the beta), it is only turned on if you choose so, and can be turned off at any time.

• Encryption on the phone: a full copy of your data is encrypted (AES-256) on the phone before sending, with a key derived from a recovery code shown only once. This code and the key are never sent: the server receives a file it cannot read, and neither can the developer.
• What the server keeps: the last 3 versions of this encrypted file, their size and upload date, and a (non-reversible) fingerprint of an identifier derived from the code, used to check that it is really you.
• Uploads: at most once a day, and only if your data has changed, or when you ask.
• Restoring: on a new phone, with your code. Without the code, the backup is lost: nobody can decrypt it.

6. Web version (optional)

The logbook also opens in a browser, at pistonbook.debirumans.fr/app/, with an account or an online backup code.

• Decrypted in the browser: the online backup is downloaded, then decrypted in the tab, as on the phone. The server still only receives encrypted files.
• Nothing is kept on the computer: the logbook lives in the tab's memory, and disappears when you close it. Only the session (the account token, or the backup code) stays in the browser if you tick "Stay signed in on this device", until you sign out. Avoid this box on a shared computer.
• No cookies, no trackers: the web version only contacts the Pistonbook server.

7. Account (optional)

An account lets you get the online backup back with an email address and a password rather than with the code. Created during the beta, it keeps the online backup free for life. Nothing in the app depends on it.

• What the server keeps: your email address, the link between this address and your online backup, the creation date, whether the account was created during the beta, and the app language (French or English), so we can write to you in that language.
• VIP status (Premium given or paid), if granted to you: its origin (beta, donation or payment), its plan (backup only, or with the web version), its start and end dates, and sometimes a short note from the developer (for example a donation reference). This information stays on the account, and disappears with it.
• Password: it never leaves the phone. The server receives a proof derived from it on the phone, and only keeps a non-reversible fingerprint. It also keeps your recovery code, encrypted on the phone with a key derived from the password: without the password, neither the server nor the developer can open it or read the backup.
• Emails: only a 6-digit code when you create the account or forget your password, and a notice when the password changes, when you ask for the account to be deleted (with the date), when you cancel it, and when the account is deleted. Never any advertising or newsletter.
• Sessions: a fingerprint of each signed-in phone's token, erased when you sign out or after 6 months without use.

8. Permissions requested

• Internet: completing vehicle sheets (see above).
• Notifications and phone start-up: servicing and renewal reminders, scheduled on the phone and rescheduled after a restart.
• Biometrics: unlocking the app with your fingerprint, if you turn it on.
• Vibration: accompanying notifications.

Photos, scans and files go through the system's tools (camera, file picker, scanner): Pistonbook has no access to your gallery.

9. Retention and deletion

Your data stays on the phone until you delete it. Deleting a vehicle or an entry erases it. Uninstalling the app or clearing its data erases everything, with no recovery possible outside your backups.

The Pistonbook server keeps no data about you, except the encrypted online backup if you turn it on, the account if you create one, and the OBD2 logs you choose to send (90 days). The backup is deleted from the server as soon as you turn it off in the app, and automatically after 6 months without an upload.

The account, if any, stays until you delete it in the app (Account tab, or Settings → Backup and data → Account). Your devices are then signed out straight away, and the account is erased 30 days later, with the email address, the VIP status and the linked backup. During these 30 days, the address stays reserved, and you can cancel the deletion by signing in again with your password. Without the app, see Delete your account. A sign-up never confirmed with the code received is not stored: the pending request erases itself, at the latest the next day.

10. Your rights

The developer holds no readable data about you, apart from an account's email address if you create one: everything can be viewed, corrected and exported in the app, and the online backup and the account can be deleted from the app (Settings → Backup and data). For any question, write to the contact address above. You can also contact the CNIL, the French data protection authority (cnil.fr).

11. Children

Pistonbook is meant for drivers and vehicle owners. It is not intended for children.

12. Changes

Any change to this policy is published on this page, with its date, and announced in the app when it changes what leaves the phone.