Private by design.

GuitarHarbor is a guitar practice app. It is designed to work without a GuitarHarbor account, advertising or third-party tracking. Practice preferences stay on your device.

Effective date: 24 October 2026 · Publisher: Tim Grootes, trading as Bumblly

The short version

No GuitarHarbor account is required.
Practice preferences and progress stay on the device.
Purchases, if any, are processed by Apple through the App Store.
No advertising SDK and no cross-app tracking.

What the app stores

GuitarHarbor stores practice preferences and progress locally on your device so your coaching loops stay available offline. Depending on your Apple backup settings, the operating system may include local app data in an iCloud or computer backup.

Permissions

Microphone: the tuner and chord check ask for microphone access. Audio is analysed live on your device to detect pitch and chords; it is never recorded to storage, uploaded or shared. You can decline or revoke the permission at any time; the rest of the app keeps working. The app does not use the camera or health data.

Purchases

Apple processes subscriptions and one-time purchases through the App Store. GuitarHarbor may read StoreKit entitlements to unlock Pro. It does not receive payment-card details. See Purchase records below.

Purchase records

Two limited, non-identifying records help us understand purchases. Neither contains a name, email address, device identifier, installation identifier, advertising identifier or Apple Account details, and the server does not log the IP address for these requests.

Purchase status from Apple. Apple sends signed App Store Server Notifications when a purchase, refund or renewal change happens. We store the notification type and subtype, product, App Store country, offer type and times rounded to the hour. Apple's original transaction ID is stored only as a keyed hash.
Purchase context from the app. When you buy, the app creates a new random code for that purchase only and gives it to Apple with the purchase. The app sends the same code with the app version, chosen plan, paywall variant, App Store country and a rough time-since-install range (0 days, 1–3, 4–7, 8–30 or more than 30 days). The code is not reused and is not linked to your device.

These records are used only in aggregate to improve GuitarHarbor.

No advertising or tracking

The current app is designed without an advertising SDK, analytics SDK, account system or developer-operated cloud sync. It does not sell personal data.

Contact and changes

For privacy questions, contact hello@bumblly.com. For product support, visit GuitarHarbor Support.

This page will be updated when GuitarHarbor's data practices materially change. The effective date at the top shows the latest revision.