Crescendo

Privacy Policy

Last Updated: December 2025  |  Version: 1.0

The Short Version

Crescendo is built privacy-first. Your data stays on your device. We don't collect, track, or sell anything.

Table of Contents

Introduction

Crescendo ("we," "our," or "the app"), developed by Crescendo Piano LLC, is a piano learning application that displays sheet music and helps you practice reading music notation. This privacy policy explains our data practices in plain language.

Our philosophy: We built this app for people who want to learn piano without being tracked, analyzed, or monetized. Privacy isn't a feature we added—it's how we designed the app from day one.

Data We Do NOT Collect

We want to be explicit about what we don't do:

What We Don't Do Details
No trackingWe don't track you across apps or websites
No analyticsWe don't use Google Analytics, Firebase, Mixpanel, or any analytics service
No advertisingWe don't show ads or share data with ad networks
No device fingerprintingWe don't collect device identifiers or create device profiles
No crash reportingWe don't send crash reports to external services
No usage statisticsWe don't monitor how you use the app
No data transmissionNothing leaves your device

We have not collected, sold, or shared any personal information in the preceding 12 months.

We do not collect sensitive personal information as defined by the California Privacy Rights Act (CPRA), including Social Security numbers, precise geolocation, racial or ethnic origin, religious beliefs, genetic data, biometric information, health information, or information concerning sex life or sexual orientation.

Data Stored Locally on Your Device

The app stores the following data only on your device:

Practice Data

  • • Practice session history
  • • Performance statistics
  • • Progress tracking

User Preferences

  • • App settings
  • • MIDI device preferences
  • • Display options

Music Library

  • • Imported files
  • • Piece metadata
  • • Thumbnail previews

How It's Stored

  • Database: SQLite database in the app's private storage
  • Preferences: SharedPreferences (Android) / UserDefaults (iOS)
  • Files: App-private file storage

Why We Store This Data

All local data exists solely to provide the app's core functionality—tracking your practice progress, displaying your music library, and remembering your preferences. This is the minimum data needed for the app to work as you expect.

Legal Basis (GDPR): Legitimate interest—we process this data locally on your device to provide the practice tracking functionality you requested when you installed the app.

This data never leaves your device. We have no servers, no cloud storage, and no way to access your information. When you practice, only you know.

How to Delete Your Data

You have complete control over your data:

Delete All Data

  • Android: Settings > Apps > Crescendo > Storage > Clear Data
  • iOS: Settings > Crescendo > Reset App Data, or delete and reinstall the app

Delete Specific Data

  • Practice history: Settings > Data > Clear Practice History
  • Individual pieces: Long-press a piece in Library > Delete

Uninstall

Uninstalling the app permanently deletes all associated data from your device.

Third-Party Services

We use no third-party services that collect data.

Service Type Our Status
AnalyticsNone
AdvertisingNone
Crash reportingNone
Social media SDKsNone
Payment processorsApp Store / Play Store only

Open-Source Libraries

We use open-source software libraries to build the app. These libraries run entirely on your device and do not transmit any data:

  • State management (flutter_riverpod) — Manages app state locally
  • Database (drift) — Stores practice data in local SQLite
  • Sheet music display (webview_flutter) — Renders music notation
  • MIDI input (flutter_midi_command) — Connects to your keyboard
  • Local notifications (flutter_local_notifications) — Practice reminders (on-device only)

None of these libraries collect, transmit, or share your data.

App Stores

The only external parties involved are:

  • Apple App Store / Google Play Store: For app distribution. Their privacy policies govern their data collection, not ours.

Apple Privacy Policy · Google Privacy Policy

Age Requirements

Minimum Age

Crescendo is intended for users aged 13 years and older.

Region Minimum Age
United States13 (COPPA)
European Union13–16 (varies by country under GDPR)
Rest of World13

Why 13+

  • • We do not knowingly collect personal information from anyone, including children
  • • Our app functions entirely offline with local-only data storage
  • • The 13+ rating aligns with COPPA requirements
  • • EU member states set their own minimum age between 13–16 under GDPR Article 8

If You Are a Parent or Guardian

If you believe a child under the applicable age has accessed our app and you have concerns, please contact us at privacy@crescendopiano.app. Since we don't collect data, there is nothing for us to delete—but we're happy to answer any questions.

Future Account Features

When we introduce optional cloud sync, account creation will require users to meet the minimum age for their region. We will implement a neutral date-of-birth verification (not a simple checkbox) at signup to comply with COPPA requirements.

Future Features: Optional Cloud Sync

We plan to offer optional cloud synchronization in a future update. This feature does not exist yet. When implemented:

What Will Change

  • • Account creation will be optional (the app will continue to work fully offline)
  • • Accounts will require users to meet the minimum age for their region
  • • Only data you explicitly choose to sync will be transmitted
  • • You will be able to delete your cloud data at any time

What We Will Collect (Future)

  • • Email address (for account authentication)
  • • Date of birth (for age verification only)
  • • Practice data you choose to sync

Your Consent Required

Before enabling any cloud features:

  1. We will update this privacy policy
  2. You will be notified in the app
  3. You must explicitly opt in (we will never auto-enable)
  4. You can continue using the app without an account

Your Privacy Rights

Because all data stays on your device, you can exercise your privacy rights directly through your device's controls:

Right How It Applies
Right to AccessAll your data is on your device. You have full access through the app.
Right to DeletionDelete via app settings or by uninstalling.
Right to RectificationEdit your data directly in the app.
Right to PortabilityYour data is in standard SQLite format on your device.
Right to Opt OutThere's nothing to opt out of—we don't transmit data.
Right to Non-DiscriminationWe treat all users equally regardless of privacy choices.

For California Residents (CCPA/CPRA)

We do not meet CCPA thresholds (we don't collect personal information), but for transparency:

  • • We have not sold personal information
  • • We have not shared personal information for cross-context behavioral advertising
  • • We have not collected personal information from California residents
  • • A "Do Not Sell or Share" link is not required because we don't sell or share

For European Users (GDPR)

  • Data Controller: Crescendo Piano LLC (contact: privacy@crescendopiano.app)
  • Legal Basis: Legitimate interest—providing the practice tracking functionality you requested
  • Data Processing: All processing occurs locally on your device
  • Data Transfers: None—data doesn't leave your device
  • Your Rights: Exercisable through your device's controls (see table above)
  • Right to Complain: You may lodge a complaint with your local supervisory authority. Find yours here

Automated Decision-Making

We do not use automated decision-making, profiling, or algorithms that make decisions affecting you. All practice statistics are calculated locally on your device for your own use.

For All Users Worldwide

We designed Crescendo to comply with the strictest privacy standards globally by simply not transmitting data. Whether you're in California, the EU, Brazil, or anywhere else—your data stays on your device.

Security

Local Data Protection

Your practice data is protected by:

  • App sandboxing: Data is stored in the app's private storage, inaccessible to other apps
  • Device security: Protected by your device's screen lock, encryption, and security features
  • No network exposure: Data cannot be intercepted because it's never transmitted

Our Security Practices

  • • No servers to secure (because we don't have any)
  • • No databases to breach (because your data stays on your device)
  • • No credentials to protect (because we don't have accounts—yet)

Your Responsibility

  • • Keep your device secure with a screen lock
  • • Keep your device's operating system updated
  • • Be cautious about who has physical access to your device

Data Breach Notification

Since all data stays on your device:

  • • We cannot experience a breach of your practice data (we don't have it)
  • • We have no servers that could be compromised

If we ever experience a security incident affecting the app itself (e.g., malicious code in an update), we will notify users via app store updates and our website within 72 hours of discovery.

Changes to This Policy

How We Handle Updates

  • • We will update this policy if our data practices change
  • • The "Last Updated" date at the top will be revised
  • • Material changes will be announced in the app before taking effect

Version History

  • v1.0 (December 2025): Initial privacy policy
    • — Complies with Apple Privacy Manifest requirements (enforced May 1, 2024)
    • — Complies with COPPA requirements (amended July 2024)
    • — Complies with GDPR, CCPA/CPRA, and international privacy laws

Review Schedule

We review this policy at least annually, even if no changes are needed.

Contact Us

If you have questions about this privacy policy or our privacy practices:

Crescendo Piano LLC

Email: privacy@crescendopiano.app

Response Time: We aim to respond within 7 business days.

What We Can Help With

  • • Questions about this privacy policy
  • • Concerns about your privacy
  • • Requests related to future account features
  • • Reports of child users (for compliance)

Platform-Specific Information

Apple App Store

  • Privacy Nutrition Label: "No, we do not collect data from this app"
  • App Store Display: "The developer does not collect any data from this app"
  • App Tracking Transparency (ATT): Not required—we don't track users
  • Privacy Manifest: NSPrivacyTracking: false, NSPrivacyCollectedDataTypes: (empty), UserDefaults API (Reason CA92.1)
  • Age Rating: 12+ (equivalent to our 13+ policy)

Google Play Store

  • Data collected: None
  • Data shared: None
  • Data encrypted in transit: N/A (no data transmission)
  • Data can be deleted: Yes (via app settings or uninstall)
  • Content Rating: Teen (aligned with 13+ age requirement)

Compliance Summary

Regulation Our Status
GDPR (EU)Compliant—legitimate interest legal basis, local processing only
CCPA/CPRA (California)Compliant—no data collection or transmission
COPPA (US Children)Compliant—no data collection, 13+ rating
LGPD (Brazil)Compliant—local processing only
PIPEDA (Canada)Compliant—no personal data transmission
Apple App StoreCompliant—privacy manifest included
Google Play StoreCompliant—Data Safety form completed

We built Crescendo because we wanted a piano learning app that respects privacy. We're musicians and developers who got tired of apps that track everything.

Your practice sessions are personal. Your progress is yours. We don't need to know how many scales you played today or what time you practice. We just want to help you learn piano.

Your data. Your device. Your music.