Privacy Policy

47 Calculator (iOS & Android) · Last updated May 9, 2026

Summary: 47 Calculator is designed to run entirely on your device. It does not require an account, does not show ads, does not include any third-party analytics or tracking SDKs, and does not share personal information with anyone.

What the app stores on your device

All of the following stays on your device and is never sent to our servers:

• Your calculator state (registers, stack, flags, modes).
• Programs you write or import, and any files you save.
• Theme and preference settings (haptic feedback on/off, etc.).
• iOS: your App Store purchase receipt — verified locally by Apple's StoreKit framework.
• Android: your Google Play purchase status — verified locally by the Google Play Billing client.

Uninstalling the app removes all of this.

What the app sends to our server

47 Calculator communicates with our own servers for exactly two reasons:

• Tutorial content delivery. When you view a tutorial, the app may fetch its text from our servers. Each request includes an authentication header that lets our servers identify your platform (so they serve the right tier of tutorial content) and apply reasonable rate limits per source IP. The header is not personally identifying — it is not linked to your Apple/Google account, your device identity, your phone number, or any other personal identifier.
• Standard web request metadata. Our server's web logs record the IP address, request timestamp, and user-agent of each request, as any web server does. We use these only for operational troubleshooting and security; we do not combine them with other data, do not sell them, and rotate logs after 30 days.

We do not collect your name, email, phone number, contact list, photos, location, or any other personal information.

Device permissions and APIs we use

• Vibration / haptic feedback. On iOS, we use UIImpactFeedbackGenerator and related APIs — no special permission required. On Android, the keypad-tap feel uses View.performHapticFeedback, also requiring no special permission. The stronger purchase-failed cue on Android uses the VIBRATE permission (auto-granted, no runtime prompt). Vibration is local to the device; nothing is sent off-device.
• Internet access. Required to fetch tutorial content and to communicate with the App Store / Google Play Billing services. Both are described above.
• We do not request location, camera, microphone, contacts, calendar, photos, files outside the app's own sandbox, or any other personal-data permission.

Third parties

• Apple (iOS). Purchases and app distribution are handled by Apple's systems under Apple's privacy policy. We receive a purchase receipt from Apple but never any personal account information.
• Google (Android). In-app purchases and app distribution are handled by Google's Play Billing and Play Store under Google's privacy policy. The Play Billing client tells us only whether the "Pro Pack" entitlement is currently owned for the signed-in Google account on this device; we never see your card data, your Google account name, or any other Google account information.
• No advertising networks, no analytics SDKs, no crash-reporting services.

Children's privacy

47 Calculator is a general-audience utility and is not directed to children under 13. We do not knowingly collect personal information from children.

Your choices

• You can disable haptic feedback and other device-dependent features from the app's theme menu at any time.
• You can uninstall the app to remove all locally-stored data.
• The app does not send any per-user identifier to our servers, so there is nothing per-user to delete. Uninstalling the app stops your device from sending any new requests; existing web logs roll off in 30 days as described above.
• To request deletion of any data you believe we may hold about you, write to the contact address below.

Changes to this policy

If we materially change how the app handles data, we will update this page and bump the "Last updated" date above. Non-material edits (typos, clarifications) may be made without updating the date.

Contact

Questions about this policy: marceldan@dansbeesllc.com