Lagrange Files for iPhone

Privacy policy

Effective 13 November 2026. This policy covers the Lagrange app for iPhone (shown in the App Store as Lagrange Files) and this website.

Who we are

Lagrange is made by Nicola Di Placido, Italy ("we", "us"). You can reach us at support@lagrangefiles.com.

What stays on your iPhone

Everything you keep in Lagrange is stored only on your iPhone, inside the app's own storage. This includes:

• your files and folders, and any changes you make to them;
• the search index, topic tags, references, and the previous versions and Recycle bin that make Undo possible;
• your settings;
• the Private folder, which is encrypted on your iPhone and opened with Face ID, Touch ID or your code. Its key is protected by the iPhone's Keychain and Secure Enclave.

Lagrange's helpers (for example search, tidy-up suggestions, duplicate finding, the safety check and the on-device reader) run on your iPhone. They do not send your files or what they learn about them anywhere.

We cannot see any of this. We do not receive copies of your files, their names, or how you use the app.

What we collect

Nothing. Lagrange contains no analytics, no advertising, no tracking code and no third-party software that reports on you. It does not create an account. We do not sell, rent, trade or share personal data, and we do not use it for advertising.

If you write to us by email, we receive your email address and what you write, and we use them only to answer you. You can ask us to delete that conversation at any time.

Apple may give us crash reports and basic usage figures if you have chosen, in your iPhone's Settings, to share analytics with app developers. Apple provides these without identifying you; this is controlled by you in iOS and covered by Apple's privacy policy.

When Lagrange uses the internet

Lagrange works without the internet. It connects only when you ask it to do something that needs a connection:

• Downloads you start. When you download a file from a link, Lagrange connects to that website, the same way a browser would. That website sees the request (for example your IP address) under its own privacy policy.
• Optional on-device models. If you choose to download a model for the on-device helpers, it comes from the site you choose (for example Hugging Face). If you add an access token for that site, it is stored in your iPhone's Keychain.
• Cloud places you connect, such as Google Drive (below).

None of these connections go through a server of ours.

Google Drive

The Google Drive connection is coming soon. This section describes how it will work when it is available.

Connecting Google Drive is optional. When you connect it, Google asks for your permission and shows you exactly what Lagrange may access.

What Lagrange can access

Lagrange asks only for Google's narrowest Drive permission (called drive.file). With it, Lagrange can see and change:

• files you pick in Google's own file picker, and
• files and folders that Lagrange creates in your Drive for you (for example when you send a file to Drive).

Lagrange cannot browse or read the rest of your Google Drive. Lagrange may read the name and email address of the connected Google account, only to show you on your iPhone which account is connected.

How Lagrange uses it

• to download the files you choose from Google Drive into Lagrange on your iPhone;
• to upload the files you choose from Lagrange into your Google Drive;
• to list, name, copy or move those files when you ask it to.

That is all. Files travel directly between your iPhone and Google's servers over an encrypted connection. They never pass through a server of ours, and we never see them.

How it is stored

The sign-in key Google gives Lagrange is stored only in your iPhone's Keychain, on this device. Files you download from Drive are stored in Lagrange on your iPhone, like any other file. Nothing syncs by itself.

Sharing

We do not share, sell or transfer Google user data to anyone. We do not use it for advertising, and we do not use it to train artificial intelligence or machine learning models. No person reads it; we have no access to it.

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

How to disconnect

• In Lagrange, open Settings › Cloud connections › Google Drive and choose Sign out. This deletes the key from your iPhone and asks Google to revoke it.
• At any time, you can also remove Lagrange's access in your Google Account at myaccount.google.com/connections.

Disconnecting does not delete files that are already in your Drive or already downloaded to your iPhone; you decide what to keep.

Other services you may connect

If Lagrange later offers other cloud places (for example Dropbox or Microsoft OneDrive), the same rules apply: optional, only when you sign in, files directly between your iPhone and that service, keys in your Keychain, nothing shared with us. We will update this policy before such a connection is offered.

Permissions on your iPhone

• Camera and microphone: only to scan documents and take photos and videos into Lagrange when you ask.
• Face ID: only to open Private. Your face data is handled by iOS; Lagrange never receives it.
• Photos and files from other apps: only the items you choose to bring in.

Keeping your data and deleting it

Your data stays on your iPhone until you delete it. You can:

• delete any file or folder in Lagrange (it goes to the Recycle bin, which you can empty);
• sign out of a cloud connection, which deletes its key from your iPhone;
• delete the Lagrange app, which removes the files stored inside it. iOS can keep Keychain entries after an app is deleted, so sign out of cloud connections first, or remove access in your Google Account as described above.

Your iPhone's own backups (iCloud or computer) may include Lagrange's files, under Apple's terms and your settings.

Security

Lagrange keeps keys in the iPhone Keychain, encrypts Private on the device, and uses encrypted connections (HTTPS) for every download and cloud transfer. No method is perfect; if you find a security problem, please write to us.

Children

Lagrange is a general-purpose app and is not directed at children under 13. We do not knowingly collect information from anyone, including children.

Your rights

Because we do not collect or store your personal data, there is usually nothing for us to show, correct or delete. If you have written to us, you can ask for a copy of that conversation or for it to be deleted. If you live in the European Union or the United Kingdom you also have the right to complain to your data protection authority.

This website

This website has no cookies, no analytics and no third-party scripts. Like any website, the hosting provider (Cloudflare) processes basic technical data, such as IP addresses, to deliver pages and protect against abuse.

Changes to this policy

If we change how Lagrange handles data, we will update this page and its date before the change takes effect, and say so in the app's release notes.

Contact

Nicola Di Placido · support@lagrangefiles.com