Privacy Policy

1. Introduction

Crankshaft is a music curation application developed and operated by Crankshaft LLC, a Georgia limited liability company. This Privacy Policy describes how Crankshaft collects, uses, stores, and protects information in connection with your use of the Crankshaft iOS application (the "App").

We take your privacy seriously. Crankshaft is designed with a privacy-by-architecture philosophy: the core intelligence of the App — including your behavioral affinity ledger, your interaction history, and your personalized music profile — is processed and stored entirely on your device. We do not sell your personal information. We do not use your data for advertising.

Please read this policy carefully. By downloading or using the App, you acknowledge that you have read and understood this Privacy Policy.

2. Information We Collect

2.1 Information You Provide Indirectly Through Use of the App

Crankshaft does not require account creation and does not ask you to submit personal information directly. However, the App collects the following categories of information automatically as a result of your use:

Apple Music Library Metadata

Crankshaft accesses metadata associated with your Apple Music library, including song titles, artist names, album names, genre classifications, and duration. This access occurs through Apple's MusicKit framework and is subject to your Apple Music subscription and the permissions you grant the App. Crankshaft does not access the audio content of your music — only the descriptive metadata associated with it.

Behavioral Interaction Data

Crankshaft records how you interact with the App, including: volume adjustment events and their timing and velocity; skip events and the temporal position within a track at which they occur; track completion events; manual affinity signals ("Crank" events); playback session data including track sequences and session duration. This data is the foundation of your personalized music profile (your "Musical Soul") and is stored locally on your device.

Anonymous Session Telemetry

Crankshaft collects anonymous, non-identifiable session-level data to measure app engagement and improve the user experience. This data includes session duration, track completion counts, user interaction event counts, manual affinity signal counts, time-of-day bucket, and app version. Each session is assigned a randomly generated identifier that is discarded after transmission and never stored or linked to any prior session. This telemetry does not include track titles, artist names, affinity scores, ledger content, or any information that could identify you or your music preferences. Session telemetry is processed by PostHog, a third-party analytics provider, under contractual obligations of confidentiality. PostHog's privacy policy is available at posthog.com/privacy.

Crash and Diagnostic Data

If the App crashes or encounters an error, Apple's built-in crash reporting infrastructure may collect diagnostic information and transmit it to Apple in accordance with Apple's Privacy Policy and your device's analytics sharing settings. Crankshaft LLC does not independently collect or receive crash data through any third-party SDK. Any diagnostic information collected through Apple's platform does not include your behavioral interaction history or your music affinity profile.

2.2 Information We Do Not Collect

Crankshaft does not collect:

• Your name, email address, or any contact information
• Your location data
• Your Apple ID or Apple Music account credentials
• Payment information of any kind
• The audio content of any music files or streams
• Information about other applications on your device
• Any data from users we know to be under the age of 13

3. How We Use Your Information

The information Crankshaft collects is used exclusively for the following purposes:

• To operate the App's core music curation engine, including building and maintaining your personalized affinity profile on your device
• To improve the accuracy of music recommendations over time based on your interaction history
• To diagnose and resolve technical errors and crashes
• To maintain the technical stability and performance of the App

We do not use your information for advertising, marketing, user profiling for third-party purposes, or sale to third parties in any form.

4. On-Device Data Processing and Storage

The core of Crankshaft's intelligence — your behavioral affinity ledger, your interaction history, your genre preference profile, and your personalized music curation data — is processed and stored entirely on your device. This data does not leave your device under the current version of the App.

Your affinity ledger is stored in the App's local Documents directory and is subject to standard iOS data protection. If you delete the App, this data is deleted with it. If you restore your device from a backup, your affinity ledger may be restored depending on your iCloud backup settings.

We are committed to maintaining on-device processing as the architectural foundation of Crankshaft. Any future feature that would involve transmitting your behavioral data off your device will be disclosed in an updated Privacy Policy, and where required by applicable law, will require your affirmative consent prior to implementation.

5. Apple Music and MusicKit

Crankshaft integrates with Apple Music through Apple's MusicKit framework. Your use of Apple Music within the App is also governed by Apple's Privacy Policy and Apple Media Services Terms and Conditions. Crankshaft does not control Apple's data practices and encourages you to review Apple's privacy documentation at apple.com/privacy.

Crankshaft requests access to your Apple Music library solely to enable music curation and playback functionality. The App does not transmit your Apple Music library data to Crankshaft LLC or any third party.

If you revoke the App's Apple Music permissions through your device settings, the App's core functionality will be unavailable.

6. Data Sharing and Disclosure

Crankshaft LLC does not sell, rent, license, or otherwise transfer your personal information to third parties for their independent use.

We may disclose information in the following limited circumstances:

• With service providers who assist us in operating the App, including PostHog (anonymous session analytics), under contractual obligations of confidentiality and solely for the purpose of providing those services
• If required by applicable law, regulation, legal process, or governmental request
• To protect the rights, property, or safety of Crankshaft LLC, our users, or the public, where permitted by law
• In connection with a merger, acquisition, or sale of all or substantially all of our assets, in which case your information would remain subject to the protections of this Privacy Policy or a successor policy providing equivalent protection

We will notify you of any material change in how your information is handled through an updated Privacy Policy posted within the App.

7. Children's Privacy

Crankshaft includes a Parent Mode feature designed to filter explicit content during family listening sessions. However, the App is not directed at children under the age of 13, and we do not knowingly collect personal information from children under 13.

If you believe that a child under 13 has provided personal information through the App, please contact us at the address below and we will take prompt steps to delete that information.

For users in the European Economic Area, we do not knowingly process personal data of children under the age of 16 without verifiable parental consent.

8. Data Retention

Your behavioral affinity data is stored locally on your device for as long as the App is installed. You may delete this data at any time by deleting the App from your device.

Crash and diagnostic data processed through Apple's built-in crash reporting infrastructure is subject to Apple's data retention policies, which are governed by Apple's Privacy Policy and your device's analytics sharing settings.

9. Your Privacy Rights

Depending on your jurisdiction, you may have certain rights with respect to your personal information, including the right to access, correct, or delete information we hold about you, and the right to object to or restrict certain processing activities.

Because Crankshaft's core behavioral data is stored locally on your device and is not transmitted to or retained by Crankshaft LLC, you exercise primary control over that data directly through your device. You may delete your affinity data at any time by deleting the App.

For any other privacy rights requests, please contact us using the information in Section 12.

California residents may have additional rights under the California Consumer Privacy Act (CCPA). If you are a California resident and wish to exercise any applicable rights, please contact us at the address below.

10. Data Security

We implement reasonable technical and organizational measures to protect the information the App collects against unauthorized access, disclosure, alteration, or destruction. Your on-device behavioral data is protected by standard iOS data protection mechanisms, including device encryption when your device is locked.

No method of electronic storage or transmission is completely secure. While we take your data security seriously, we cannot guarantee absolute security.

11. Future Data Practices and Policy Updates

Crankshaft is an evolving product. We anticipate that future versions of the App may include features that involve transmitting certain data off your device — for example, to enable cross-device synchronization of your affinity profile or to support future functionality. We commit to the following with respect to any such changes:

• We will update this Privacy Policy prior to implementing any material change in data collection or transmission practices
• We will provide notice of material changes through the App and, where required by law, will seek your affirmative consent before collecting or transmitting new categories of data
• We will not retroactively apply new data practices to data collected under this Policy without your consent

We encourage you to review this Privacy Policy periodically. Continued use of the App after a posted update constitutes acceptance of the revised Policy.