KNOWLEDGE BASE

NuDefndr uses Apple's Sensitive Content Analysis framework - a privacy-first, on-device Machine Learning system. Scanning occurs entirely within your iPhone's secure enclave, without ever transmitting data externally. No internet connection is required. This zero-trust architecture ensures your photos never leave your device.

NuDefndr uses Apple's official Machine Learning framework. It looks for sensitive or intimate content based on visual analysis. You can mark items as "safe" to exclude them from future scans.

The app analyzes each photo locally using on-device ML. Photos identified as potentially sensitive are shown to you in a list. You can then review each one and decide to either: mark it as safe, leave it in your library, or move it to the encrypted Vault (Pro feature).

Vault (Premium) is an encrypted container built into NuDefndr for ultra-sensitive content. When you move images to Vault, they're encrypted instantly using ChaCha20-Poly1305 with 256-bit keys and isolated within a sandboxed secure enclave on your device. Vault can only be accessed with FaceID or Touch ID, offering seamless yet strong protection for your most private data.

Vault uses ChaCha20-Poly1305 with 256-bit keys—the same encryption standard used in modern VPNs, TLS, and secure messaging apps. 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 - not even us.

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 need to keep photos long-term, export them from Vault before switching devices.

Yes. Analysis happens on-device. NuDefndr stores only app settings locally. No photos or analysis results are stored by the app persistently or transmitted externally. We don't have servers to send your data to - it all stays on your iPhone.

Free users can perform 2 scans per week (resets at midnight each Monday) and scan 'Today' only (last 24 hours). You can mark a limited number of items as safe per week. This lets you try the core functionality before upgrading.

Pro users get unlimited scans, all time ranges (7 days, 30 days, 90 days, 1 year, 2 years, or entire library), unlimited "mark as safe" actions, plus exclusive features:

• • Smart Auto-Scan: Automatically scans new photos in the background
• • Encrypted Vault: 256-bit ChaCha20-Poly1305 encryption with FaceID
• • Instant Privacy Blur: Hide all thumbnails from view
• • App Lock: Require FaceID to open NuDefndr
• • All Premium Themes: Stealth, Ghost, Tactical, De-Ad, Cyber