Last updated: September 21, 2026.
Cléa is a free piano-learning app for beginners. This page explains in plain terms what data is processed and how.
No account, no tracking
Cléa never asks for sign-up, a name, an email address or a date of birth. There is no advertising, no ad tracker, no analytics tool (e.g. Google Analytics), and no data is ever sold to a third party.
Microphone (« real piano » feature)
The microphone is used, only if you turn it on, to recognise notes played on a real piano during a lesson. This recognition happens entirely on your device (real-time audio analysis in the browser): no sound is ever sent, transmitted or stored on a server. Nothing is kept after the lesson.
Teacher's voice (text-to-speech)
Lesson text (never personal data) is sent to Google Cloud Text-to-Speech to generate Cléa/Clédo's voice. The resulting audio files are cached on our servers (Google Cloud, European Union) to avoid re-generating the same audio every time — this cache is not linked to any individual user.
Preferences stored on your device
A few preferences (language, letter/solfège notation, chosen teacher, lesson progress) are stored locally in your browser (localStorage) so the app remembers your choices. This data stays on your device and is never transmitted.
Children
Cléa can be used by children without any account creation and without collecting personal data about them.
Hosting
The app is hosted on Google Cloud (Europe region, europe-west1).
Contact
Questions about this policy? Write to jmetro.run@gmail.com.