Privacy Policy

Last updated: 21 October 2026

This policy explains what information Kerf: Construction Calculator ("Kerf", "we", "us") handles when you use the Kerf app for iPhone and Android (the "App") or visit https://kerf.pixoby.space (the "Website"). Kerf is made by Pixoby.

The short version: Kerf works without an account. Your measurements, Jobs, material lists, price book and estimates stay on your phone. We do not sell your information and the App shows no ads.

1. Information that stays on your device

Calculator inputs and results, the paper tape, Jobs, material lists, notes and photos you attach to a Job, your price book, presets, your logo for estimates and the PDFs you create are stored on your device. We do not receive them. If you use Backup or Export, the file goes wherever you choose to save or share it.

2. Information we receive

• Optional sign in: if you choose to sign in with Apple or Google (used to carry Pro between iPhone and Android), we receive an account identifier and the email address the provider shares with us, which may be a private relay address. This is stored on our server at kerf-api.pixoby.space.
• Purchases: Apple and Google process payment. We receive purchase records (product, date, store transaction identifiers) through RevenueCat so we can unlock and restore Pro. We never see your card details. RevenueCat also stores your app language and the analytics and attribution install IDs, so purchases can be counted in those tools.
• Usage analytics: Google Firebase Analytics receives app events (for example, which calculators are opened, app version, device model, operating system, language, country derived from IP address) linked to a random app-instance identifier.
• Crash reports: when the App crashes or hits an error, a report with technical details (stack trace, device and app version) is sent to GlitchTip, our error tracking service.
• Install attribution: we use Tenjin to learn which campaign, if any, led to an install. Kerf never asks to track you and never reads your device's advertising identifier. Tenjin counts installs through Apple's SKAdNetwork and an app-specific identifier. On Android, the advertising ID is not collected. Tenjin uses the Google Play install referrer.
• Notifications: Kerf sends no notifications and creates no push token.
• Support email: if you write to us, we receive your email address and what you send.

3. How we use it

• To unlock, restore and carry Pro across your devices
• To find and fix crashes and to learn which features are used, so we improve the right ones
• To measure whether our marketing works
• To answer support requests and meet legal obligations

4. Sharing

We do not sell or rent personal information and we do not show ads. We share information only with the service providers named above (Apple, Google, RevenueCat, Google Firebase, Tenjin, GlitchTip and our hosting providers), who process it on our behalf, and when required by law.

5. The Website

The Website does not require an account. It may use Google Analytics to count visits and store your light or dark theme choice in your browser. Store links take you to the App Store or Google Play, which have their own privacy policies.

6. Retention

Data on your device is removed when you delete the App or its data. Our server keeps your account record until you delete it. Purchase records at RevenueCat and at Apple or Google are kept for tax and accounting and so a purchase can be restored. Analytics and crash data are kept for a limited period set in those services and then deleted.

7. Deleting your account

If you signed in, open Settings, then Account, then Delete account in the App. You can also email info@pixoby.space from the email address you signed in with. We delete your account record, your email address and the server copy of your purchase record, and we revoke Kerf's access to your Sign in with Apple account. Jobs stay on your phone until you delete them or the App. Full steps and what is kept.

8. Your rights

Depending on where you live (for example under the GDPR or California law), you may have the right to access, correct, delete or export your personal information, and to object to or restrict some processing. Email us to make a request. You may also complain to your local data protection authority.

9. Children

Kerf is a tool for construction work and is not directed to children under 13. We do not knowingly collect information from children.

10. Security and transfers

Information sent to us travels encrypted. Our providers may process it in the United States and other countries, with safeguards such as Standard Contractual Clauses where required.

11. Changes

If we change this policy we will update the date above, and tell you in the App if the change is significant.

12. Contact

Pixoby, info@pixoby.space