Last updated: July 20, 2026
DuctSizer Pro works 100% offline. It does not have a backend, does not require an account, and does not include any analytics or tracking software. This page explains exactly what that means for your data.
None. DuctSizer Pro does not collect, transmit, or share any personal information, usage data, device identifiers, or location data. The app never requests network/internet permission, because it never needs one.
Your preferences — unit system, duct material, air condition, language, and numeric keypad setting — are saved locally on your device using the operating system's standard local storage. This data:
DuctSizer Pro does not integrate any third-party SDKs, analytics platforms, advertising networks, or crash-reporting services.
DuctSizer Pro is sold as a one-time purchase through the Apple App Store or Google Play Store. Payment processing is handled entirely by Apple/Google under their own privacy policies — the developer never sees or stores your payment information.
DuctSizer Pro is an HVAC engineering tool and is not directed at children. Since the app collects no data from any user, this applies equally regardless of age.
If this policy ever changes — for example, if a future version adds an optional feature that touches data — this page will be updated and the "last updated" date above will change accordingly.
Questions about this policy can be sent to duonghedspi@gmail.com.