Terms of Use

Effective date: 24 September 2026 · String Tuner 1.0 and later

1. Who provides the app

lapnito.cz s.r.o. (Lapnito Development Studio), company ID (IČO) 19537441, Czech Republic (“we”). Contact: tom@lapnito.cz.

2. Agreeing to these terms

By downloading, installing or using String Tuner you agree to these terms. If you do not agree, please do not use the app. If you use the app on behalf of a school or another organisation, you confirm that you may accept these terms for it.

3. What String Tuner is

String Tuner is a tuner and practice tool for violin, viola, cello, double bass, guitar, ukulele and mandolin. It offers a needle tuner, reference tones, a guide to tuning by ear, a drone, a metronome, an intonation trainer, historical temperaments and other tuning systems, import of Scala scales, a teacher mode that shares setups by QR code, an Apple Watch app and a home-screen widget.

The app is free in full: no purchases, no subscription, no account and no advertising. It works offline and stores everything on your device.

4. Your licence

We grant you a personal, non-exclusive, non-transferable, revocable licence to use the app on devices you own or control, for your own practice and — for teachers — for teaching your students. The app is licensed, not sold. All rights not expressly granted remain ours.

5. Readings are guidance, not a calibrated measurement

The tuner measures what your device's microphone hears. Accuracy depends on the microphone, background noise, how the instrument is played and the device itself; Bluetooth microphones add delay. String Tuner is a musician's tool, not a certified or calibrated measuring instrument.

The tables for historical temperaments and for Arabic, Turkish, Persian and Indian tuning systems are written conventions. Players and traditions depart from them, and the app says so where you choose them. Scales you import are used exactly as their files state; we do not check their musical correctness.

6. Look after your instrument and your hearing

• Strings can break. Make sure the instrument and tuning chosen in the app match what you are tuning. Tuning a string far above its intended pitch can break it or damage the instrument. Tune up gradually and follow your teacher's or luthier's advice.
• Mind the volume. The drone, reference tones and metronome can be played through headphones for a long time. Keep the volume at a comfortable level.
• Stay aware. Do not use the app where looking at your phone or watch could put you or others at risk.

7. Teacher mode

Teachers can store results their students hand in and, if they wish, type a student's name next to them. That name stays only on the teacher's device and is never put into a QR code. A teacher who stores students' names or exports results is responsible for doing so lawfully — for example with the consent that their school or local law requires for pupils — and for any file they export and share.

8. Your content

Scales you import, assignments you create and anything you type belong to you or their authors. Import only files you are allowed to use. We never receive your content; it stays on your device.

9. What you may not do

• use the app unlawfully, or to infringe the rights of others;
• reverse engineer, decompile or disassemble the app, except where the law expressly allows it;
• sell, rent, sub-licence or redistribute the app or parts of it;
• remove or change copyright notices, trademarks or these legal texts.

10. Third parties

You get the app from the App Store or Google Play, whose own terms also apply. The system rating prompt, Siri and your device backups are provided by Apple or Google. On Android, QR codes are read by Google ML Kit through Google Play services, under Google's terms (see the privacy policy). We are not responsible for those services, or for apps and services you choose in the share sheet.

11. App Store users

If you downloaded the app from Apple's App Store: these terms are between you and us, not Apple, and we — not Apple — are responsible for the app and its content. Apple has no obligation to provide maintenance or support. To the extent the law provides any warranty, if the app fails to conform to it you may notify Apple, and Apple's sole obligation is to refund any purchase price (the app is free). We, not Apple, are responsible for handling any claims relating to the app, including product-liability claims, claims that it fails to meet legal or regulatory requirements, consumer-protection claims and third-party intellectual-property claims. You confirm that you are not located in a country subject to a U.S. Government embargo and are not on a U.S. list of prohibited or restricted parties. Apple and its subsidiaries are third-party beneficiaries of these terms and may enforce them against you. Apple's Standard Licensed Application End User License Agreement applies where these terms say nothing.

12. No warranty

The app is provided free of charge, “as is” and “as available”. To the extent permitted by law, we give no warranty that it will be error-free, uninterrupted, compatible with your device, or suitable for a particular purpose.

13. Limitation of liability

To the extent permitted by law, we are not liable for indirect or consequential loss, for damage to instruments or strings, or for loss of data stored in the app. All data lives only on your device, so we cannot restore it — back up your device if your practice history matters to you.

Nothing in these terms limits liability that cannot be limited by law — such as liability for intent or gross negligence, or for harm to life or health — or your mandatory rights as a consumer.

14. Changes and ending

We may update, change or stop offering the app, and we may update these terms; the current version is always on this page with its effective date. You may stop using the app at any time by uninstalling it. If you seriously breach these terms, your licence ends and you must stop using the app.

15. Law and disputes

These terms are governed by the law of the Czech Republic. If you are a consumer, you keep the protection of the mandatory law of the country where you live, and you may bring a claim in the courts there. Consumers may also use out-of-court dispute resolution through the Czech Trade Inspection Authority (Česká obchodní inspekce — ADR). If any part of these terms is invalid, the rest still applies.

16. Contact

lapnito.cz s.r.o., Czech Republic, IČO 19537441 · tom@lapnito.cz · Support