CellopediaPractice Room

Terms of Service

Cellopedia Practice Room
Kozlov Cello Studio LLC, Maryland, USA

Last updated: 22 October 2026
Effective: 11 September 2026

Automatic renewal: please read this first

Your subscription renews automatically until you cancel.

This is repeated in section 4 with the rest of the billing terms. It is here as well because California and several other states require it to be the first thing you read, and because it is the part people most often wish they had known.

1. Agreement

These terms govern your use of Cellopedia Practice Room at practice.cellopedia.org, operated by Kozlov Cello Studio LLC (“I”, “me”). By creating an account or using the service, you agree to them.

Questions: hello@cellopedia.org.

2. Who may use this

You must be 18 or older to create an account. If you are under 18, please do not sign up.

One account per person, for your own use. Do not share your account or your sign-in codes.

3. What you get

Without an account, free forever

The metronome, tuner, drone, and slow-downer.

With a free account, free forever

Everything above, plus the full practice session flow, recording yourself during a session with playback and comparison, your recordings library across days, and the pieces marked free in the library. Recordings stay on your device only. They are never uploaded, and you can download any take. Your practice history shows the sessions from the last 7 days; older sessions are kept, not deleted, and Premium shows your whole history.

With Premium

Everything above, plus the full repertoire library, your whole practice history, cloud sync and backup of your practice sessions, and page scanning (in beta: up to 10 pages a month, or 12 on the yearly plan), with an AI clean-up of the lines that look wrong (section 5).

I may add, change, or remove features. If I remove something material that you are paying for, I will tell you in advance, and you may cancel and receive a refund for the unused part of your current period.

4. Subscriptions, payment and cancellation

Prices

Premium costs $17.99 per month or $149 per year, in US dollars. Checkout displays and settles in US dollars everywhere. If your card is in another currency, your bank does the conversion. Sales tax or VAT is added on top of the price shown where the law requires me to collect it.

If I change prices, I will tell you at least 30 days beforehand. A change never affects a period you have already paid for, and you may cancel before it takes effect.

The free trial

New accounts may start a 14-day free trial. A card is required to begin it. Nothing is charged on the day you start.

When the 14 days end, the subscription begins automatically and your card is charged, at the price of the plan you selected, unless you cancel first. Stripe will email you before the trial converts.

One trial per account.

Canceling

You may cancel at any time, from the billing portal on your account page. It takes two clicks and requires no email, no phone call, and no explanation.

Changing plan

Monthly subscribers can switch to annual from the billing portal. Stripe credits the unused part of your month against the annual price and shows you the exact amount before you confirm.

Switching from annual to monthly is not offered. To move to monthly, cancel at the end of your annual period and subscribe monthly afterwards. You keep full access and all your data until then.

Failed payments

If a payment fails, Stripe will retry over several days and email you. You keep access during that time. If it ultimately fails, the subscription ends and you return to the free tier.

Refunds

Subscription payments are not refundable, except where the law requires it (which includes statutory cancellation rights in the UK, EU and elsewhere), and except in the three cases these terms promise one: I remove a material feature you are paying for (section 3), I close your account for a breach that was not deliberate (section 7), or I change these terms and you leave because of it (section 12). Refunds in those cases go to your original payment method; if one applies to you and has not arrived, contact us at hello@cellopedia.org.

If you delete your account while holding a paid subscription, the subscription is set to end when the period you have paid for ends, and is never charged again. Nothing is cut short and nothing is refunded, but deleting the account means you cannot use the remaining time. To use it, cancel first and delete your account when the period ends.

If something has gone wrong, contact us at hello@cellopedia.org. I would rather sort it out than stand on this clause.

If you are in the UK or EU

You have a statutory right to cancel a distance contract within 14 days without giving a reason. By starting your subscription or trial you ask me to begin providing the service immediately. If you cancel within those 14 days, you owe a proportionate share of the price for the time you had the service and I refund the rest. On a free trial nothing has been charged, so there is nothing to refund. After those 14 days, the cancellation terms above apply.

5. Your content

Your practice sessions, notes, and recordings belong to you. I claim no ownership.

Your recordings never leave your device, so no permission over them is needed or taken. For sessions and notes, you grant me only the permission needed to run the service: to store them and show them back to you, and to sync them between your devices if you have Premium. That permission ends when you delete the content or your account.

I cannot listen to your recordings: they are never on my servers.

Scores you add yourself, from your own MusicXML files, stay on your device in the same way: they are never uploaded, and I claim no rights in them.

Scanning a page is a beta feature. It works best on clean, printed cello parts in bass clef. Photos are not accepted; a PDF made with your phone’s own scanner works well. Tenor and treble clef, handwritten music and older editions often do not scan well yet, and any result may need correcting before it is right. You may scan up to 10 pages in a calendar month on the monthly plan, or 12 on the yearly plan, or 2 pages during a free trial; each page of a PDF you tick counts as one. Only scan music you have the right to use: the Practice Room does not check, and you are responsible for the copies you make. The scanned result is yours and I claim no rights in it. It is kept on your device; a copy of the page’s notes passes through my server for the AI clean-up described below and is cleared afterwards, as the Privacy Policy explains in section 4b.

The AI clean-up. After a page is scanned, free automatic checks on my server look for lines that seem wrong: a bar that does not add up to the meter, a line the scanner lost or left empty, a note outside the cello’s range, or a sign that a clef change was missed. Only those lines are sent to an AI model, Claude Opus 5.5 from Anthropic, each with a picture of the line and the notes the scanner read in it, to be corrected. A page with nothing flagged is never sent to the AI; it is ready at once. The clean-up usually takes under an hour. A line whose first answer cannot be used is sent once more, which can add up to an hour. A line the AI has not answered about an hour after the page was sent is asked again at once, outside the batch. If the AI has not answered within four hours, the plain scan stands.

For 24 hours after a scan you can also ask about particular bars: “Tell the AI what’s wrong” takes a short note of up to 300 characters about the music, such as “bars 13 to 16 have wrong notes”, and the lines holding those bars go to the AI with your note. After 24 hours the page image is gone and you can correct notes by downloading the MusicXML file, fixing it in MuseScore (free) or another notation program, and replacing the score with the edited file.

The AI’s result may contain mistakes. It can misread a note, a rhythm or a clef, and it can leave a wrong bar as it is. Check every corrected page against your printed part before you rely on it. A line the AI could not settle is left as the scanner read it and outlined for you to check.

Limits. The clean-up uses the same page allowance as scanning: the 10 or 12 pages a calendar month, or 2 pages during a free trial, named above. “Tell the AI what’s wrong” is limited to 20 requests in a calendar month, or 3 requests during a free trial. A request the AI could not answer is given back, up to five times in a month. I also keep a cost limit for each account’s month. If your clean-ups reach it, scanning still works, but without the AI until the first of the next month, and the app tells you so. The AI clean-up is a beta feature. I may change these limits or withdraw it; section 3 says what happens if I remove something you are paying for.

The pictures, the notes and your notes to the AI are sent to Anthropic in the United States, with no name, email address or account identifier. The Privacy Policy, section 4b, says exactly what is sent and how long it is kept.

6. My content

The service, its design, and the teaching materials in it (the engraved scores, my reference recordings, the accompaniments, and the written guidance) belong to me or are used with permission.

You may use them for your own practice. You may not redistribute them, share your account so others can reach them, or use them in your own teaching materials or products without my written permission.

Musical works in the public domain are public domain. My particular editions, engravings, recordings and accompaniments are not. Scores you add yourself are yours, not mine, and nothing in this section applies to them.

7. Acceptable use

Do not:

If you do these things I may suspend or close your account. Where reasonable I will contact you first, and where I close a paid account for these reasons I will refund the unused portion of your period unless the breach was deliberate.

8. Deleting your account

You can delete your account at any time from your account page. It is permanent and it takes your practice history with it, along with the recordings on the device you delete from; recordings on your other devices stay until you delete them there.

Records of payments already made are kept as tax law requires, as explained in the Privacy Policy.

9. Availability

I aim to keep the service running. I cannot promise it will never be unavailable, and I may take it down for maintenance. Where an outage is planned I will give notice if I can.

Parts of the app work offline once loaded. Features needing the internet, such as sync, subscription changes and loading new pieces, will not.

10. Disclaimers

The service is provided as it is. I make no warranty that it will be uninterrupted or error-free, or that it will improve your playing.

Scanning and the AI clean-up are beta features. Their results may be wrong, and I do not warrant that a scanned or corrected score matches your printed part; section 5 says how to check it.

The help assistant on the Help page explains how to use the app from the app’s own reference text, and its answers may be wrong. It gives no advice about playing, and it cannot change anything in your account; for that, write to hello@cellopedia.org.

This is a practice tool, not a teacher and not medical advice. If you feel pain while playing, stop, and see a qualified teacher or a doctor. Nothing here replaces working with a teacher in person.

Some jurisdictions do not allow the exclusion of certain warranties. Where that is so, the exclusions above do not apply to you.

11. Limitation of liability

To the extent the law allows, my total liability to you for any claim arising from the service is limited to the amount you have paid me in the twelve months before the claim.

I am not liable for indirect or consequential losses, including lost practice data. Recordings exist only on your own devices by design. Downloading the takes that matter to you is how they are kept, and every take has a download button for exactly that reason.

Nothing here excludes liability for death or personal injury caused by negligence, for fraud, or for anything else that cannot lawfully be excluded.

12. Changes to these terms

I may update these terms. If a change materially affects you, I will tell you by email or in the app at least 30 days before it takes effect. Continuing to use the service after that means you accept the updated terms. If you do not, you may cancel and delete your account, and I will refund the unused portion of your current period.

13. Governing law and disputes

These terms are governed by the laws of the State of Maryland, United States, and disputes will be brought in the courts of Maryland.

If you are a consumer, this does not deprive you of the protection of the mandatory laws of your country of residence, and you may bring proceedings in your local courts where the law gives you that right.

There is no arbitration clause and no class-action waiver in these terms.

14. Contact

Kozlov Cello Studio LLC
Maryland, United States
hello@cellopedia.org

Credits

Synthesized cello: FluidR3_GM SoundFont, MIT license. The license text is at /soundfonts/FluidR3_GM-LICENSE.txt.

Page scanning: Audiveris 5.11.0, an open-source optical music recognition program by Herve Bitteur and contributors, under the GNU Affero General Public License version 3. It runs unmodified on my scanning server, as a separate program. Its source code for exactly the version I run is at https://github.com/Audiveris/audiveris/releases/tag/5.11.0 and the license is at https://github.com/Audiveris/audiveris/blob/5.11.0/LICENSE.

AI clean-up by Claude Opus 5.5 from Anthropic. The model runs on Anthropic’s servers and is reached through its API; only the flagged lines of a scanned page are sent to it, as the Privacy Policy describes in section 4b.

The help assistant is answered by Claude Haiku 4.5 from Anthropic, reached through the same API; only your question, the last two exchanges of the same visit and the app’s reference text are sent to it, as the Privacy Policy describes in section 4c.

PDF pages for scanning are drawn on your device by pdf.js (pdfjs-dist 6.4) from Mozilla, under the Apache License, Version 2.0: https://github.com/mozilla/pdf.js/blob/master/LICENSE.

Its decoders for JBIG2, CCITT fax and JPEG 2000 images come from PDFium and OpenJPEG, under BSD licenses, with the qcms color module under the MIT license; they are served from this site together with their license files: https://practice.cellopedia.org/pdfjs/wasm/LICENSE_JBIG2, https://practice.cellopedia.org/pdfjs/wasm/LICENSE_OPENJPEG and https://practice.cellopedia.org/pdfjs/wasm/LICENSE_QCMS.