TargetLock

TargetLock is an AR distance measurement app for iPhone and iPad. It helps you estimate the distance to a visible person, pet, or object when you know the target's real-world height.

The app uses a simple two-tap measuring flow. Point the camera at the target, tap the top, tap the bottom, choose a height preset or enter a custom height, and TargetLock calculates an estimated distance using ARKit camera tracking and camera intrinsics.

What's new in version 1.1:
- Clearer measurement results with confidence labels and practical tips
- Height entry in meters, centimeters, or feet and inches
- Remembered custom height for faster repeat measurements
- Current-session history with details and sharing
- Share All export for session measurements
- Optional grid and crosshair overlays for alignment
- Haptic feedback setting
- First-launch tutorial and improved in-app help
- App version and build shown in Settings

TargetLock is designed for quick field estimates, learning, home use, pet and people distance checks, outdoor notes, and situations where a dedicated rangefinder is not available.

Key features:
- ARKit-based camera tracking
- Two-tap top-to-bottom measurement
- Height presets for adults, children, and dogs
- Custom height input in multiple units
- Distance display in meters, feet, or both
- Confidence percentage and Good/Fair/Low label
- Tips for improving low-confidence measurements
- Undo and Reset controls
- Optional grid and crosshair guides
- Pinch-to-zoom with corrected distance calculation
- Session measurement history
- Share individual measurements or the full session
- Works offline after installation

TargetLock uses stadiametric rangefinding: it compares the known real-world height of the target with the target's height on screen and the camera focal length provided by ARKit. The result is an estimate, not a certified survey measurement.

For best results:
- Keep the target fully visible
- Tap the true top and bottom carefully
- Use the most accurate target height available
- Measure in good lighting
- Keep the device steady
- Avoid steep camera angles
- Move closer when the target is very small on screen

Privacy is simple: TargetLock works locally on your device. It does not require an account, subscription, internet connection, location access, analytics SDK, advertising SDK, or backend service. Camera access is used for the live AR view and on-device measurement. Camera images and measurements are not uploaded by the app.

TargetLock is an estimation tool for general utility and education. It is not intended for medical, surveying, construction-safety, emergency, weapon, or certified professional measurement use.