The short version: Musician Toolkit does not collect, transmit, or store any personal data on external servers. Everything — including your microphone audio — is processed on your own device. We don't know who you are, how you use the app, or how often you use it.
Musician Toolkit is developed and published by Hrdlicka Apps LLC, based in Iowa, USA. You can reach us at support@hrdlickaapps.com.
The Tuner and Pitch Trainer tools use your device's microphone to detect the pitch of what you're playing or singing, so the app can show you a tuning needle or score a practice attempt. This audio is analyzed instantly, in memory, on your device, and is never recorded to a file, saved, or transmitted anywhere. Musician Toolkit has no backend server, so there is nowhere for that audio to go even if we wanted to send it.
The app asks for microphone permission the first time you open the Tuner or Pitch Trainer, with an in-app explanation shown before the system permission prompt. You can deny this permission and still use the Metronome fully — it needs no microphone access at all.
To be explicit: this pitch and frequency analysis is not biometric identification. Musician Toolkit does not create, extract, or store a voiceprint or any other biometric identifier. Audio exists only transiently in memory while a note is being analyzed, and is discarded immediately after — it is never converted into a persistent, re-identifiable representation of your voice.
We collect nothing. Musician Toolkit does not have a backend server, does not create user accounts, and does not transmit any information about you or your usage to Hrdlicka Apps LLC or any third party.
A small amount of data is saved locally on your device so the app can remember things between sessions: your preferences (A4 tuning reference, haptics on/off, default metronome settings), your calibrated vocal range, and your Pitch Trainer practice history and scores. None of this ever leaves your device, and none of it is tied to any account, because there is no account system.
This matches the Data Safety section Musician Toolkit publishes on Google Play in full: it discloses no data collected and no data shared, and it will stay that way for as long as this policy says the same thing.
The Metronome can tap out the beat using your device's vibration motor. This is a local hardware call only and involves no data of any kind.
Like most Android apps, Musician Toolkit's local app data may be included in your device's own built-in backup to your Google account, the same way your phone backs up its other apps and settings. This is a feature of your Android device, not something Hrdlicka Apps does — we have no access to your backups and no way to see this data.
Musician Toolkit does not integrate any third-party analytics, crash reporting, or advertising SDKs. We do not use Firebase, Amplitude, Mixpanel, Crashlytics, or any similar service. We don't know how many people use the app, what they do in it, or who they are.
Musician Toolkit's pitch detection is classical digital signal processing (the YIN algorithm), not a trained machine-learning model. No audio, from you or anyone else, is used to train any AI system, and none ever will be — there is no server for training data to be sent to in the first place.
The CCPA/CPRA applies to businesses that meet certain revenue or data-volume thresholds. Hrdlicka Apps LLC does not meet any of them, and in any case Musician Toolkit collects no personal information to sell, share, or opt out of. If you send a Global Privacy Control signal, there is nothing for it to act on — but we honor the spirit of it regardless, since we already share and sell nothing.
The GDPR applies where personal data belonging to EU residents is collected or processed. Musician Toolkit is available on Google Play in the EU, but availability alone doesn't trigger the GDPR — actual data processing does, and there is none here. We have no need for a Data Protection Officer, an EU representative, or an Article 13 notice-at-collection mechanism, because there is no personal data collected to give notice about.
Musician Toolkit is a general-audience music practice tool suitable for all ages. Because we collect no personal data whatsoever, there is no risk to users of any age. Musician Toolkit does not collect, use, or disclose personal information from any user, including children under 13.
Because all data is stored on your device, you are in complete control. Your Pitch Trainer practice history can be cleared at any time from the app's Settings screen. To remove everything else, simply delete the app from your device. Nothing is retained on any server because nothing was ever sent to one.
If we update this Privacy Policy, we will update the "Last updated" date at the top of this page. Material changes will be communicated through an app update notice. Continued use of Musician Toolkit after any changes constitutes acceptance of the updated policy.
Questions about this policy? Email us at support@hrdlickaapps.com. A real person will read and respond.