Privacy Policy

Piano Libre. Last updated: September 2026.

The whole policy in one sentence: what you play stays on your device, and this page lists every single exception.

Piano Libre is built local-first. Your sheet music, your MIDI playing and your practice history are held in your device's own storage. If a behaviour is not described below, the app does not do it.

1. What stays on this device

Your sheet music files. Anything you import (.musicxml, .mxl, .mid) is stored in your browser's local database (IndexedDB) and is never uploaded. Not to us, and not to anyone else.
The titles of your own files. A file you imported may be named after a student, a lesson, or anything else. When you open a piece from My Scores, the usage statistics record only that a personal score was opened — never its name, and never its composer.
Your MIDI playing. Notes from a connected keyboard are processed in the moment, to follow the score and show feedback. They are not recorded, stored or transmitted.
Your practice history. Which pieces you played, how long, how accurately, which bars cost you the most, your XP and your streak. All of it lives in your device's storage.

2. What leaves this device

Each row below is a separate feature, switched on and off independently. The stamp says what this build of the app actually does — it is read from the app's own configuration, not typed into this page by hand.

What	When it leaves	In this version
Anonymous usage statistics	Only if you switch sending on. See section 3.	off by default
An account (email address, subscription state, course progress)	Only if you subscribe to Piano Libre Pro. See section 5.	not checked
A PDF you choose to convert	Only when you import a PDF of sheet music. See section 6.	not checked
Data collected by an advertising network	Only if the app shows advertising. See section 7.	not checked

3. The usage statistics

They exist for one purpose: to find out which parts of the app get used and where people get stuck, so it can be improved. They are written to a local database on your device (app_analytics_db).

Attached to every event

Field	What it is	How long it lasts
`sessionId`	A random identifier for the current visit. It is not tied to you — it is created fresh each time and cannot connect one visit to another.	Discarded when you close the tab or app
`cohortDate`	The date you first used the app (day only, e.g. `2026-08-25`). It tells us whether newcomers keep playing.	Kept on your device
Device	Broad type (iPad, iPhone, Android or desktop), window size, pixel density, whether the screen is touch-capable, and the language your device is set to.	Per event

This is deliberately coarse. There is no device serial number, no advertising identifier, and no fingerprint.

The events themselves

Event	What it records
`app_opened`	That the app was opened.
`onboarding_started`, `onboarding_completed`, `onboarding_skipped`	Whether you finished the introductory questions, and at which step you left. Includes your answers: whether you have a MIDI keyboard, and the skill level you chose.
`piece_opened`	Which piece was opened. For catalogue pieces: title, composer and difficulty — these are our own public-domain data. For your own scores: only that it came from My Scores.
`practice_started`	The practice mode and which hand you chose. The piece title is included only for catalogue pieces.
`practice_completed`	How long you played, the accuracy percentage, how many notes were right and wrong, and your daily streak.
`practice_abandoned`	That you left before the end, how long you had played, and how far into the score you were. This is how we find the passages where people give up.
`score_uploaded`, `omr_transcription_started`, `omr_transcription_completed`, `omr_transcription_failed`	That a personal score was added or a PDF was transcribed, and whether it worked. Not the file, and not its name.
`metronome_toggled`, `pinch_zoom_used`, `midi_init_attempt`	That the feature was used.
`ajustes_abertos`	That you opened the badge listing what the app adjusted in a piece, and how many adjustments that piece had. Never the piece's name.

Where they go

Nowhere, unless you say so. Sending is off by default, and off means nothing leaves the device — the statistics are written to a local database and stay there.

You can turn sending on under Settings → Share anonymous usage data, and turn it off again at any time. While it is off, the app refuses to transmit even if a collection server has been configured: the check sits in the sending code itself, not in this page.

As of this version, no collection server is configured at all. If we ever do configure one, this page will name the provider and where its servers are before any data is sent.

4. What the app never does

It never listens to your room. The app does not access your microphone.
It never uploads a score you imported, nor its file name.
It never sells or shares your data with data brokers.
It never tracks you across other apps or websites, and it asks for no advertising identifier.
It never builds a profile of who you are. The statistics above cannot be connected to a person, because the app has no identifier for a person.

5. Accounts and Piano Libre Pro not checked

This section describes a feature that is not part of this version of the app. There is no account, no sign-in, no subscription and no payment. It is described here so that you can read what will change before it changes, and this page is stamped from the app's own configuration rather than from memory.

Piano Libre Pro is a paid subscription. The free app needs no account; subscribing creates one, and the account carries exactly two things:

Who you are to us: the email address you sign up with, and the state of your subscription.
Your course progress: which lessons and exercises you have completed, so the study path continues on your other device.

The boundary that does not move: your practice content stays on the device. The server knows who subscribed. It does not know what you played — not the pieces, not the bars you struggled with, not the recordings, and not the scores you imported.

Payment. Purchases made inside the app are handled by Apple or by Google, under their own privacy policies. We receive whether you are subscribed; we never receive your card number.

6. Converting a PDF not checked

This section describes a feature that is not part of this version of the app. PDF import is switched off.

When you import a PDF of sheet music, the file is sent to our conversion server, turned into a playable score, and the result is stored on your device.

The PDF is used for that conversion and nothing else.
It is deleted from the server once the conversion finishes, and is not kept for training, review or any other purpose.
Nothing else about the file — not its name — is recorded.

If you do not import a PDF, no file ever leaves your device.

7. Advertising not checked

This section describes a feature that is not part of this version of the app. The app contains no advertising and no advertising SDK.

When advertising is present, an advertising network is a separate company processing data under its own policy, and this page will name it and link to that policy.

Where the law requires consent, you are asked before any advertising data is collected, and refusing is a real option: the app works the same.
Refusing consent does not turn advertising on in a quieter way. It turns the collection off.
Subscribers see no advertising at all.
Advertising is never targeted using your practice history, because the advertising network never receives it.

8. Deleting everything

Clearing your browser's site data for this app removes all of it at once: your imported scores, the usage statistics, your preferences, your streak, and the offline copy. On iPad and on Android, deleting the app does the same.

There is no recovery, and that is the cost of there being no account. Nothing is held elsewhere for us to restore, because nothing is held elsewhere.

If you hold a Piano Libre Pro account, you can ask for it to be deleted, and deleting it removes the email address and the course progress held on the server.

9. Children

Piano Libre is made for teenagers and adults. It is not directed at children under 13, and we do not knowingly collect personal information from them.

10. Contact

The contact channel is not open yet — there is no address to write to, and publishing one that does not resolve would be worse than publishing none. Help → Report a problem, inside the app, produces a diagnostic report you can copy and keep. As soon as an address exists, it appears there and here.

11. Changes to this policy

The date at the top changes with the text. The sections above that describe a feature carry a stamp read from the app's own configuration, so a feature cannot be switched on without this page saying so.