Frequently Asked Questions

NuDefndr leverages Apple’s Sensitive Content Analysis framework — a privacy-first, on-device AI system. Scanning occurs entirely within your iPhone or iPad’s secure enclave, without ever transmitting data externally. No internet access is required. This zero-trust architecture ensures that your personal media never leaves your device. Learn more in the Apple developer documentation.

Vault (Premium) is a military-grade encrypted container built into NuDefndr for ultra-sensitive content. When you transfer images to Vault, they’re encrypted instantly using AES-256 and isolated within a sandboxed secure enclave on your device. Vault can only be accessed with biometric Face ID, offering a seamless yet unbreakable layer of defense for your most private data.

Vault uses end-to-end AES-256 encryption — the same standard trusted by governments and security agencies. Encryption and decryption occur entirely on your device, with no external servers involved. Vault contents are stored within a protected directory inaccessible to other apps or systems. Without your biometric authentication, no-one can access your data — and that’s by design.

Vault data cannot be recovered when changing devices, restoring from backup, or reinstalling the app. This is by design for maximum security — encryption keys are stored exclusively in your device’s Keychain with hardware-level protection that prevents transfer between devices. If you restore NuDefndr from an iCloud backup on a new device, you may see vault thumbnails that cannot be decrypted. The app will show ‘Unable to decrypt’ messages after 5 seconds of trying. Pro users can use the ‘Clear Vault’ feature to remove inaccessible photos and start fresh on the new device.

iOS security and privacy design prevents third-party apps like NuDefndr from automatically intercepting content you share directly to other apps (like Messages, Telegram, WhatsApp, etc.). The operating system handles its own built-in Sensitive Content Warnings for certain apps. The NuDefndr Share option acts as a manual check: if you are concerned about an image, you can choose to share it to NuDefndr first from the Share Menu. NuDefndr will then analyze it and show a warning if needed before you proceed.

Free users can scan the last 7 days of photos. Pro users get extended ranges including Last 24 Hours, Last 30 Days, Last 90 Days, Last Year, Last 2 Years, and All Photos. Pro users also get Auto-Scan which automatically scans new photos in the background using the last 7 days range for optimal performance.

Photos might be skipped for two main reasons:
1. iCloud Photos: If the ‘Scan iCloud Photos’ setting is off (default), photos stored only in iCloud won’t be downloaded or scanned to save time and data.
2. Already Scanned (Incremental Scan): When scanning ‘All Time’, photos unmodified since the start of the last completed scan are skipped for efficiency. All scans are local.

Pro users can blur sensitive thumbnails in both the Review and Vault screens for additional privacy. The blur feature can be toggled manually using the eye icon, or Pro users can enable ‘Always Blur by Default’ in Settings > Appearance to automatically blur thumbnails when entering these screens.

Yes. Analysis happens on-device. NuDefndr only stores settings and the last scan timestamp locally. No photos or analysis results are stored by the app persistently or transmitted externally. Vault photos are encrypted and stored securely on your device only. Please see our Privacy Policy for full details.

Yes. Limited key components of NuDefndr are open source on GitHub to provide complete transparency about how the app works. You can view the code that handles sensitive content detection and verify that we have no data collection or network transmission functionality whatsoever.

The name NuDefndr is a playful word with a few different interpretations. You can see it as "nude finder" (for identifying sensitive content), "nude defender" (for protecting those images), or even "new defender" of your privacy. We designed it to be a bit ambiguous, giving users a way to interpret it that best suits them.