Obelisk Agency ("we", "us", "our") is committed to protecting your privacy. This Privacy Policy explains how Structor ("the App") handles your information.
1. Data Collection
Structor is designed with a privacy-first, offline-first approach. We do not collect personal information. All calculations and data processing happen locally on your device.
The App may store the following data locally on your device only:
- App preferences (theme, language, unit system, field mode)
- Calculation history you choose to save
- Favorited calculators and recently used calculators
- Job projects and custom material prices you enter
- Per-calculator saved input values for convenience
- Technical crash diagnostics when a non-fatal error occurs
We have no access to your calculations, project names, or any personal data you enter into the App.
2. Data Storage
All data is stored exclusively on your device using Android's Room database and DataStore. We do not operate servers that store user data. When you uninstall the App, all locally stored data is automatically removed.
3. Data Sharing
We do not share, sell, or transfer any user data to third parties. The only data that may be shared externally is:
- Calculation results you explicitly choose to export or share (copy to clipboard, Android share sheet, PDF export)
- Anonymous crash diagnostics collected by Firebase Crashlytics (see Third-Party Services)
- Aggregate, anonymous usage events collected by Firebase Analytics (see Third-Party Services)
- Data collected automatically by the advertising SDK (see Third-Party Services)
4. Offline Functionality
All 65+ calculators work entirely offline. Structor does not require an internet connection to function. The only network activity comes from loading advertisements and sending anonymous crash reports when connected.
5. Engineering Disclaimer
Structor is an estimation and reference tool. Calculation results are approximations based on standard industry formulas and published reference tables (NEC, IEC, IBC, IRC, ACI, Eurocode, and equivalent international standards).
Results must not be used as the sole basis for structural, electrical, or plumbing decisions. Always verify calculations with a licensed professional in accordance with your local building codes.
6. Third-Party Services
The App integrates three third-party services, all provided by Google: AdMob (advertising), Firebase Crashlytics (crash reporting), and Firebase Analytics (aggregate usage analytics).
Google AdMob (Advertising)
The free version displays a banner advertisement on the home screen and occasional interstitial advertisements. AdMob may collect:
— Advertising identifiers
— Device information (model, OS version)
— IP address (for ad serving and geolocation)
— Usage data for ad personalization
You can opt out of personalized ads in your device's Settings > Google > Ads.
For more information, see Google's Privacy Policy.
Firebase Crashlytics (Crash Reporting)
The App uses Firebase Crashlytics to receive anonymous crash reports. Crashlytics collects:
— Crash stack traces and exception details
— Anonymous installation identifier
— Device model and operating system version
— The calculator identifier that triggered the crash (e.g., "concrete_volume")
Crashlytics data is anonymous and used only to diagnose and fix software defects. It is never linked to your identity or sold to third parties.
Firebase Analytics (Aggregate Usage)
The App uses Firebase Analytics to understand which calculators are used and how often, so we can prioritise improvements. Analytics collects:
— Anonymous app instance identifier
— Screen views and aggregate event counts (e.g., "calculator_opened", "result_exported")
— Device model, OS version, app version, country (derived from IP, then discarded)
— No calculation inputs, project names, or any content you enter into the App
Analytics data is anonymous and aggregated. It is never linked to your identity or sold to third parties.
For more information about both Firebase services, see Firebase's Privacy and Security.
7. Permissions
The App requests only the permissions it needs:
- Internet: Required solely to load advertisements and send anonymous crash reports. All calculators work without an internet connection.
- Network state: Used by the advertising SDK to avoid loading ads when offline.
The App does not request access to your contacts, location, camera, microphone, files, or any other sensitive permissions.
8. Children's Privacy
Structor is a professional tool intended for construction contractors, engineers, tradespeople, and DIY homeowners aged 18 and over. The App does not collect personal information from anyone, including children under 13, and does not knowingly target children. The App does not require account creation, login, or personal data entry.
9. Security
We implement reasonable measures to protect locally stored data:
- All calculation data stays on your device in app-private storage
- Android Auto Backup preserves your history and projects across device transfers when enabled
- Advertising and crash SDK traffic uses HTTPS
- No authentication credentials or payment data are ever collected or stored
10. Your Rights
Clear data: Clear the app's cache and data through Android Settings
Uninstall: Uninstall the App to remove all locally stored data
Opt out of personalized ads: Reset or disable your Advertising ID through your device settings
Disable crash reporting and analytics: Turn off "Usage and diagnostics" in your device's Google settings
11. GDPR & International Users
If you are located in the European Economic Area, the United Kingdom, Switzerland, or another jurisdiction with data protection laws, you have the right to request information about the data processed by the advertising, analytics, and crash reporting SDKs. On first launch in these regions the App presents a Google User Messaging Platform (UMP) consent form for personalized advertising; if you decline, the App falls back to non-personalized ads. You can revisit your consent at any time from the in-app Settings screen. Because we do not maintain any user accounts or server-side records, Obelisk Agency does not store personal data that could be disclosed or deleted on request. For data processed by Google services, contact Google directly through the links above.
12. Changes to This Policy
We may update this Privacy Policy from time to time. Changes will be posted on this page with an updated date. Your continued use of the App after changes constitutes acceptance.