Privacy Policy
Musami · Effective November 8, 2026 · Version 2026-11-08
The short version
- You can use Musami without an account. Then your progress stays on your device, and we receive nothing about you unless you see the Pro screen or buy Pro on iPhone. Everyone except people we know are under 13 sees the Pro screen once at the end of setup. Apple and our subscription service handle the purchase.
- An account is optional, and only for people 16 and over. It keeps a copy of your progress so you can pick it up on another device. You sign in with Apple or Google; we never see a password.
- We ask before collecting usage data, and you can say no. It goes with a random ID, not your name, email or account. We never ask anyone we know is under 16.
- No ads, no tracking across other companies' apps or websites, and we never sell or share your data for advertising.
- You can download your data or delete your account in the app at any time.
- Accounts are only for people 16 and over. If we know you are under 16, you can't make an account, and nothing you do leaves your device except what a purchase needs. If we know you are under 13, nothing leaves the device at all.
1. Who we are
Musami is made by WavePrism Labs LLC, a California limited liability company ("we", "us"). We decide how your personal data is used (the "controller").
- Address: 2108 N St, Ste C, Sacramento, CA 95816
- Email: privacy@waveprismlabs.com (privacy) and support@waveprismlabs.com (everything else)
- Phone: (415) 907-0709
We have no data protection officer; the law doesn't require one for a service like ours. For Quebec, the person in charge of the protection of personal information is our managing member, who you can reach at privacy@waveprismlabs.com.
2. Without an account
Everything you do in the app is saved on your iPhone, in the app's own storage: your lessons, quiz results, review schedule, daily minutes and streak, practice notes, songs you make in the Studio, your answers, and your settings. It doesn't leave your device, with these exceptions:
- Buying Pro on iPhone. Apple handles the payment. When you see the Pro screen, restore a purchase or buy, the app talks to our subscription service, RevenueCat, using a random customer ID (see section 5). Everyone except people we know are under 13 sees the Pro screen once at the end of setup, which can come before the app knows your age. If you never see the Pro screen and never sign in, the app sends nothing to RevenueCat.
- Usage data, only if you say yes (section 6).
- Your age range stays on your device (section 8).
- Messages and reports you send us. If you email us or use the report form in Settings, we receive what you send (section 4).
The app also keeps a log of its own events on your device (for example "lesson finished"). The log itself is never sent. Usage data is sent separately, and only from the moment you say yes. The log is included in Download my data, and Reset all data removes it.
If you back up your iPhone, for example with iCloud Backup, the backup may include the app's data. That backup is yours, and we can't read it.
3. With an account
An account is optional, and only for people 16 and over (section 8). You create one with Sign in with Apple or Sign in with Google. We never receive or store a password.
What we receive when you sign in
- Your email address, from Apple or Google. With Sign in with Apple you can choose "Hide My Email": we then receive a private relay address (…@privaterelay.appleid.com) that forwards to you, and we never see your real address.
- An account ID that Apple or Google gives us for you, used only to sign you in.
- We don't keep your name or picture. Google sends your name and a link to your profile picture with every sign-in; our database deletes them before anything is saved. We never ask Apple for your name.
- When you accepted the Terms, and which versions of the Terms and this policy you were shown.
- When the account was made and last used, and technical logs of sign-ins and requests, which include your IP address (section 11).
- Your account ID goes to RevenueCat when you sign in, so that Pro follows your account, even if you never open the Pro screen (section 5).
What syncs to your account
While you are signed in, the app keeps a copy of your learning on our database so your devices stay in step:
- your lessons and quiz results;
- your review schedule (how well you remember each idea);
- your daily activity (minutes, lessons and reviews per day), from which the streak is worked out;
- the milestones you have reached, and the badges you have earned with the day you earned each one;
- your notes on the practice cards ("I played it", tempo);
- the songs you make in the Studio, and which ones you deleted;
- your answers from about the last 30 days (older answers stay only on the device that gave them);
- your learning choices: instrument, daily goal, level and starting point, left-handed fretboard, the guitar track, whether the daily streak is on, where you heard about Musami if you answered that question during setup, and your answer to the usage-data question (section 6);
- the badges you have earned and the day you earned each one;
- a few flags, such as "has finished the first lesson".
Each signed-in device also gets a random device ID when you sign in, so two devices don't overwrite each other. It isn't linked to your device's hardware, and names like "This iPhone" stay on the device.
Not synced: your display, sound and haptics settings, reminders, your age range, and the app's own event log. They stay on each device.
Where it is kept
Our database runs on Supabase, in its East US (North Virginia) region. Through the app, only you can read your rows: the database checks every request against your sign-in. We can reach them ourselves, and we do so only to run the service or to deal with a report of illegal content, a legal order, a privacy request or a security problem.
Signing out
Signing out ends your session on that device. Your progress stays on that device so you can carry on without an account. On a shared device, use Settings › Account and data › Reset all data after signing out.
4. What we use your data for, and the legal basis
| What | Why | Legal basis (EU and UK) |
|---|---|---|
| Account: email, account ID, terms accepted | To give you an account and keep your learning in step across devices | Performing our contract with you (Art. 6(1)(b)) |
| Synced progress and songs | The same | Contract (Art. 6(1)(b)) |
| Purchases and subscription status | To give you Pro and restore it | Contract (Art. 6(1)(b)) |
| Purchase records and the terms you were shown | To keep a record of what was bought and shown, to deal with refunds and disputes, and to count subscriptions and renewals in RevenueCat's reports | Our legitimate interest in running the business and proving what was agreed (Art. 6(1)(f)) |
| Usage data | To see which lessons are too hard or unclear, how features such as reminders and the Pro screen are used, and what to improve | Your consent (Art. 6(1)(a)); you can withdraw it any time |
| Security and service logs | To keep the service secure and working | Our legitimate interest in a secure, working service (Art. 6(1)(f)) |
| Messages you send us | To answer you | Contract, or our legitimate interest in answering (Art. 6(1)(b) or (f)) |
| Your age range | To apply the age rules in section 8 and to check that you are old enough to agree to usage data | Our legitimate interest in protecting minors (Art. 6(1)(f)) |
| Reports of illegal content | To review them and act, as the EU Digital Services Act requires | Legal obligation (Art. 6(1)(c)) |
| Website visits: hosting logs and visit totals | To serve the website, keep it secure and see how many people visit | Our legitimate interest in a secure website and in knowing how it is used (Art. 6(1)(f)) |
| Inactivity warnings and the record of deleted accounts | To warn you before deleting an unused account, and to prove a deletion happened | Our legitimate interest in keeping accurate records (Art. 6(1)(f)) |
| Privacy requests and consent records | To answer you and to prove what you chose | Legal obligation under the GDPR (Art. 6(1)(c) and Art. 7(1)) |
We don't use your data for advertising, we don't build marketing profiles, and we make no automated decisions with legal or similarly significant effects. The review schedule decides which ideas to practice next; it is a learning feature only.
If you are under 18 and the law where you live doesn't let you make a contract yourself, we rely instead on our legitimate interest in giving you the account or purchase you asked for (Art. 6(1)(f)).
You don't have to give us your name, your email or any other details to use the free lessons. The app does send RevenueCat a random customer ID when the Pro screen opens at the end of setup (section 2). Without an account your progress doesn't sync, and without a yes no usage data is sent. To buy Pro you need an Apple Account.
5. Purchases (iPhone)
Pro is sold in the iPhone app through Apple's in-app purchase. Apple takes the payment; we never see your card or payment details. Apple acts as its own controller for the purchase (see Apple's privacy policy).
We use RevenueCat to check what you have bought. RevenueCat receives from Apple your purchase and subscription history for this app (product, dates, renewal, refunds), and from the app a customer ID: a random ID, or, if you are signed in, your account ID. It also receives basic technical details such as the app version, the iOS version, your App Store country and, as with any internet connection, your IP address. When you buy, we also note on the customer which version of the paywall and which terms and privacy links you were shown, as proof of what you agreed to; for anyone we know is under 18 we note nothing. We don't give RevenueCat your email or name. We also use RevenueCat's reports to see how many people subscribe, renew and cancel, including how groups of yearly subscribers hold up over time.
The website doesn't sell anything.
6. Usage data (optional, off until you say yes)
At the end of a lesson, after your first, we ask once: "Share usage data?". "No thanks" and "Share usage data" are equally easy. You can change your answer any time in Settings › Share usage data.
- Before you say yes, nothing is sent, and nothing logged earlier is sent later.
- If you say yes, the app sends events to PostHog, our analytics service, in its US region. They cover lessons and answers ("lesson started", "answer right or wrong", time on a screen, "lesson left at screen 4"), your choices during setup (including where you heard about Musami, sent once if you answered), and app events such as the Pro screen being opened, a trial or purchase, a reminder being sent or opened, signing in or out, and a song being created. Each event carries a random ID for this installation, a random ID for this session, the app version and the time. No name, email, account ID or anything you type is sent, and the events are never joined to your account. Because the installation ID stays the same over time, we treat these events as personal data.
- No cookies, no session recording, no "autocapture" of what you tap, and no location. PostHog doesn't store the IP address the request comes from, and we have turned off its lookup of a location from that address.
- If you switch it off, sending stops at once and anything not yet sent is dropped.
- We keep your answer (yes or no, when, and which version of this policy) on your device and, if you are signed in, with your account, so your choice follows you. It is never stored with the installation ID.
- We never ask anyone we know is under 16. The app sends no usage data for them, even if a "yes" was recorded before their age was known. If you are 16 or 17, "No thanks" comes first, and if you say no we won't ask again.
7. Reminders
If you turn on the daily reminder, your device shows it. The reminder time and the schedule stay on your device. If you share usage data (section 6), the events can include the time you chose during setup and whether a reminder was sent or opened. The app works fully without reminders. If you buy the annual plan, the app also asks to send one notification about 30 days before it renews. That notice is set on your device, and nothing about it is sent to us. Under 18, reminders, the daily goal and the daily streak stay off unless you turn them on in Settings. Under 13 there are none (section 8).
8. Children and age
Musami is a general music theory course for teenagers and adults, not a service directed at children. Younger people may use it too, so once we know someone is under 13, nothing about them leaves their device, and once we know someone is under 16, only what a purchase needs does. We know a person's age only if Apple tells the app or the person answers the app's age question.
- On iPhone, the app asks Apple's Declared Age Range service for an age range each time it opens. Apple shows its own screen the first time, and you (or a parent) choose whether to share; if you choose not to, the app doesn't ask Apple again. We receive only a range (under 13, 13–15, 16–17, or 18 and over), never a birth date.
- Where Apple gives no range (an iPhone without that service, or if you choose not to share), the app asks "What year were you born?" once. It asks at setup, on the screen that offers an account, or, if you skip that screen, after your first lesson and before anything else. You can choose "Prefer not to say". We keep only the age range the year falls in, and discard the year. If both Apple's range and your answer exist, the younger one counts. On an iPhone where Apple gives no range, the Pro screen at the end of setup can come before the age question, so RevenueCat can receive a random customer ID, the technical details in section 5 and the device's IP address before we know your age.
- What we do with it: the age range only decides which features and questions apply to you, as described below. It stays on your device: it is never sent to us or to anyone else. On iPhone, the answer to the app's own question is also kept in the device's keychain (this device only, never backed up to iCloud), so deleting and reinstalling the app doesn't let anyone answer again; Apple's range is asked again instead. It is only the age range, never the year.
- If you choose not to give your age, the app treats you as a general user, the same as an adult. An account, syncing and the usage-data question are then available, because the rules below apply only when we know your age. A parent who finds an account made by someone under 16 can ask us to delete it.
- 13 to 17: you can use the free lessons, practice, review and the Studio, keep your progress on your device and buy Pro on iPhone (Apple's Ask to Buy lets a parent approve it). The daily streak, the daily goal and reminders stay off unless you turn them on in Settings, and we never suggest it. Reminders only come between 4 and 10 pm and never mention your streak. A milestone's share card appears only when you ask for it.
- From 16: you can also make an account, which keeps a copy of your progress so it can sync, and you can choose to share usage data. If we know you are under 16, you can't make an account, nothing syncs, and we never ask about usage data.
- If we know you are under 13, nothing leaves the device. Pro is for people 13 and over, so the app stops contacting our subscription service, and everything free stays free. There are no reminders, no daily goal and no daily streak. If the Pro screen opened before the app knew the age, RevenueCat already holds a random customer ID, the technical details in section 5 and any purchase made then. RevenueCat deletes them 3 years after the app last contacted it, unless a subscription is active.
- 13 to 17, only what a purchase needs: when the Pro screen opens or Pro is bought, RevenueCat (section 5) receives a random customer ID (or your account ID, if you are 16 or 17 and signed in), the purchase and technical details listed in section 5 and, as with any internet connection, the device's IP address. We use these to show the price, to process and restore the purchase, to unlock Pro and to count subscriptions in RevenueCat's reports. We never use them to contact anyone, to advertise or to build a profile, and we add no other attributes. RevenueCat works under an agreement with us and may not sell them. It deletes a random customer ID 3 years after the app last contacted it, unless a subscription is active.
- If we learn a signed-in device belongs to someone under 16, syncing stops at once, everything that device sent is deleted from our server (and the whole account, if no other device ever used it), and the device signs out. The progress stays on the device. If the device is offline at that moment, the deletion happens the next time the app opens.
- Parents and guardians: where the law requires it (for example in Texas), Apple may ask a parent to approve the app, its purchases, or a significant change to it. If a parent declines a change in the app, Musami waits on a screen that asks for approval again. If a parent withdraws approval through Apple, Apple may stop the app from opening on that device. The progress stays on the device either way. We can't cancel a subscription, so a parent should check it in Apple's settings. To ask us to delete data about your child, write to privacy@waveprismlabs.com.
- Teens' rights: if you are a teenager, you or a parent can ask us at any time to see, correct or delete personal information we hold about you. Write to privacy@waveprismlabs.com.
9. Who receives your data
We use these service providers ("processors"). Written agreements require them to protect your data to the same standard as this policy. For data from the EU and the UK, they may act only on our instructions. Elsewhere, some of those agreements also let a provider use data to keep its service secure and improve it, but never to sell it or to advertise.
| Provider | What for | Where |
|---|---|---|
| Supabase Pte. Ltd. (Singapore), on Amazon Web Services | Sign-in and the database for accounts and sync | United States (Virginia); support staff may access it from elsewhere |
| RevenueCat, Inc. | Checking purchases and subscriptions | United States |
| PostHog, Inc. | Usage data, only if you agree | United States |
| Cloudflare, Inc. | Serving the website and reporting visit totals; it sees your IP address in its network logs | Global network |
| Resend (Plus Five Five, Inc.) | Sending our emails: the warning before an unused account is deleted, and receipts for reports of illegal content | United States |
| Google LLC (Google Workspace) | Our support and privacy mailboxes | United States and other countries where Google keeps data |
Apple (App Store purchases, Sign in with Apple, Declared Age Range, notifications) and Google (Sign in with Google) act as independent controllers under their own privacy policies.
We may disclose data if the law requires it, to protect people's safety, or as part of a sale or merger of our business, in which case the buyer must honor this policy.
We don't sell your personal data or share it for cross-context behavioral advertising. We don't use advertising networks or ad-measurement tools, and the app doesn't track you across other companies' apps or websites.
10. Transfers outside the EU and UK
We are based in the United States, and our database, analytics and purchase checks run there (Supabase, PostHog, RevenueCat). If you use the app or the website from the EU or UK, your data is transferred to the United States. For each provider we rely on:
- PostHog: the EU–US Data Privacy Framework, with its UK Extension and the Swiss–US framework (PostHog is certified).
- Supabase and RevenueCat: the European Commission's Standard Contractual Clauses (controller to processor), with the UK Addendum for UK data (and, for Supabase, the Swiss addendum).
- Resend: the EU–US Data Privacy Framework with its UK Extension, and the Standard Contractual Clauses with the UK Addendum in its data processing agreement as a fallback.
- Cloudflare: the EU–US Data Privacy Framework, and the Standard Contractual Clauses in its data processing agreement.
- Google Workspace: the safeguards in Google's Cloud Data Processing Addendum, which are a recognized framework such as the Data Privacy Framework or, failing that, the Standard Contractual Clauses.
We keep a short assessment of each transfer and the extra safeguards we use: encryption in transit and at rest, only the data each provider needs, and no data on our servers about anyone we know is under 16. You can ask us for a copy of the safeguards.
11. How long we keep it
| Data | How long |
|---|---|
| Your account and synced data | Until you delete your account, or 5 years after you last used it (see the next row). "Reset progress on all devices" deletes the synced progress and songs at once. |
| Synced answers | About 30 days. A daily job removes them from our database once they are 35 days old. |
| Accounts not used for a long time | Deleted 5 years after the last time any device signed in to it opened the app or synced, with an email warning 30 days before. We keep them this long because learners often come back after a long break. An active subscription counts as use. Progress saved on your devices isn't affected. |
| Reports of illegal content | 2 years after the case is closed. |
| Database backups | Copies in encrypted backups are overwritten within 7 days. |
| Server and sign-in logs | 7 days |
| Website logs and visit totals | Cloudflare keeps its network logs only as long as it needs them to run and secure its network, under its agreement with us. It publishes no fixed period. Visit totals have no personal data. |
| Record that an account was deleted | 3 years, without your email: a one-way code made from the account ID, the time, and whether the Apple sign-in was revoked |
| Usage data (if you agreed) | 12 months, then deleted by PostHog |
| Purchase records | With an account, RevenueCat's copy is deleted when the account is deleted. Without one, RevenueCat deletes it 3 years after the app last contacted it, unless a subscription is active. Apple keeps its own records under its policy. |
| Support messages | 2 years |
| Privacy requests | 24 months after we answer |
| Your age range | On your device only. "Reset all data" keeps it, so a reset doesn't change which features apply. On iPhone, the answer to the app's own age question stays in the device's keychain after the app is deleted. The only way to remove the keychain entry is to erase the iPhone. |
| On your device | Until you delete it: Settings › Reset all data, deleting your account, or deleting the app |
12. Your rights and choices
Wherever you live, you can:
- get a copy of your data: Settings › Account and data › Download my data gives you a file (JSON) with everything on your device and, if you are signed in, your account details and everything in your account;
- correct it: change your choices in Settings;
- delete it: Settings › Account and data › Delete account (section 13), or Reset all data for what is on your device;
- withdraw consent to usage data: Settings › Share usage data;
- ask us about any of this, or to restrict or object to how we use your data, at privacy@waveprismlabs.com (Settings › Legal › Privacy requests).
You can object at any time to any use of your data that rests on our legitimate interests (section 4). Write to privacy@waveprismlabs.com. We will stop unless we have compelling grounds to continue or we need the data for a legal claim.
We answer within one month (we may extend this by two months for complex requests, and will tell you). We may ask you to confirm the request comes from the account holder, for example by writing from the account's email address. We keep a short record of each request.
EU and EEA: you also have the rights to restriction, objection and portability under the GDPR, and the right to complain to the data protection authority where you live or work.
United Kingdom: you also have the rights to restriction, objection and portability under the UK GDPR. You can complain to us at privacy@waveprismlabs.com. We acknowledge complaints within 30 days and respond without undue delay. You can also complain to the Information Commission's Office (ICO) at ico.org.uk.
United States: depending on your state, you may have rights to access, correct, delete and get a copy of your data, and to opt out of sale, targeted advertising and profiling. We don't sell data or use it for targeted advertising or profiling. Send any request to privacy@waveprismlabs.com; if we refuse, you can appeal by replying to our answer, and we will tell you how to contact your state attorney general.
California: we don't sell or share personal information as defined in the CCPA, and we don't disclose personal information to third parties for their direct marketing.
Do Not Track and Global Privacy Control: these are signals a web browser can send. The iPhone normally sends no such signal to apps. If the app does receive either signal, it never asks about usage data and sends none, whatever you answered before. The website treats every visitor the same whatever the browser sends: it sets no cookies and runs no analytics script. We don't track you across other companies' sites or apps in any case.
13. Deleting your account
In the app: Settings › Account and data › Delete account. You confirm with Apple again (or by typing DELETE for a Google account). Then, at once:
- we revoke the app's access to your Apple sign-in (when you signed in with Apple);
- we delete your RevenueCat customer record;
- we delete your account and everything synced to it from our database;
- the app removes your progress from that device.
Copies on other devices that were signed in stay on those devices until you reset them there. Copies in encrypted backups are overwritten within 7 days.
Deleting your account doesn't cancel an App Store subscription. Apple bills it and it continues until you cancel it in your iPhone's Settings › Apple Account › Subscriptions (or in the app, Settings › Subscription › Manage subscription). The app reminds you before you delete.
Usage data you have already shared isn't linked to your account, so deleting your account doesn't delete it. It is deleted after 12 months. To have it deleted sooner, send us the analytics ID shown in Download my data (the line "analyticsInstallId") at privacy@waveprismlabs.com, and we will ask PostHog to delete it. Reset all data removes that ID from your device, so copy it first.
You can also ask us to delete your data at privacy@waveprismlabs.com.
14. Security
We use encrypted connections (HTTPS) everywhere. Through the app, each person can read and write only their own rows. The app holds no secret server keys, and we collect as little as we can. No method is perfectly secure; if a breach puts your data at risk, we will tell you and the authorities as the law requires.
15. Storage on your device and the website
The website at musami.app sets no cookies, stores nothing on your device and runs no analytics script. It has no accounts and no forms. We see visit totals in Cloudflare's own traffic reports, which come from its servers and not from your device. Like any web host, Cloudflare sees your IP address in its network logs when it serves a page to you (section 9). The site's fonts are served from our own site.
16. Changes to this policy
We will post any change here with a new effective date. You can get an earlier version by writing to privacy@waveprismlabs.com. If a change is significant, the app will tell you before it applies, and where the law requires it we will ask for your consent again.
17. Contact
WavePrism Labs LLC, 2108 N St, Ste C, Sacramento, CA 95816 · privacy@waveprismlabs.com · (415) 907-0709