Cargo Measure AR Documentation

What is Cargo Measure AR?

Cargo Measure AR is a free LiDAR-powered iOS app that turns the iPhone Pro in your back pocket into a 3D cargo measuring tool. Scan real cases, build a local manifest as you walk the floor, and one-tap push every case into your Truck Packer case library, ready to drop into a load plan on the web.

Built for touring production teams (audio, video, lighting, and staging crews) and the AV rental warehouses, theatrical productions, and freight teams that move irregular gear. The app is free, measuring and file exports work without an account, and cloud sync requires an organization with Truck Packer Pro.

How It Works

1. Point the camera at an object. The app reads LiDAR depth in real time and aligns a 3D reticle to the surface in front of you.
2. Place the three base corners. Guided placement defines the rectangular footprint. After the first edge, the reticle is constrained to a 90° build line, so the footprint is always a true rectangle.
3. Set the height. A live 3D box previews the case. Each height adjustment is a separate undo-able step, so you can fine-tune freely before committing.
4. Save to the manifest. Add a name, manufacturer, category, weight, and a description. Mark whether the case can be flipped. Smart pre-fill carries your last entry into the next scan.
5. Push to Truck Packer. Every case lands in your organization's case library with categories mapped automatically (missing ones are created for you), ready to use in load plans on truckpacker.com.

Alongside the full 3D Cube mode, an Edge mode measures simple point-to-point distances and a Rectangle mode captures 2D footprints.

Measurement

• 3D surface-aligned reticle oriented to surface normals via ARKit planes + mesh
• Snap-to-corner within 5cm of existing points, with haptic feedback
• Smooth-damped cursor motion tuned to stay responsive without jitter
• 90°-constrained build line keeps footprints square after the first edge
• Ground plane lock for consistent base measurements
• Tap or drag to set height after the third corner
• Undo last point / full reset controls (height drags undo step by step)
• Post-measurement base point adjustment (drag any corner to reposition)
• Three build modes: Edge (distance), Rectangle (footprint), Cube (full 3D)
• Feet displayed as X′ Y″, never as decimal feet

Truck Packer Integration

Sign in with your Truck Packer account using Clerk. No API key, no copy-paste of tokens. Cloud features require the active organization to have Truck Packer Pro.

• Clerk native auth using the iOS SDK
• Direct Convex function calls to the same backend as the web app
• Push cases to Truck Packer: every manifest item is created in your org's case library, with categories mapped by name and missing categories created automatically. Note: pushing the same manifest twice creates duplicate cases, so push once per manifest.
• Live category sync with your org, including category colors, used in the save sheet's chip picker
• Multi-organization support with org switcher and live per-org case and pack counts
• Unit preferences sync to your Truck Packer account, so the app and truckpacker.com always agree

A REST API is also exposed at steady-beagle-345.convex.site/api/v1 for legacy integrations that need static API keys.

Manifest Management

• On-device item storage that persists without a network connection
• Editable name, manufacturer, description, category, weight, dimensions, and a flippable flag per item
• Smart pre-fill: the save sheet carries your last entry's name, manufacturer, category, weight, and flippable flag into the next scan for fast repeat entry
• Swipe to duplicate any manifest item in one gesture
• Renameable manifests; the name becomes the base of export filenames
• Export the full manifest to CSV, Excel (XLSX), or PDF via the Files app, email, or AirDrop, always with unit-aware columns
• Categories synced live from your Truck Packer organization, colors included

Architecture

Data flow

Packing algorithm (coming in a future release)

An on-device flat-row layout engine ships in the codebase but the create-pack flow is not yet enabled in 1.0; today, exports go to your case library. When it lands, the pass works like this (separate from the web app's AutoPack engine):

1. Sort floor items by category, then depth, then weight descending
2. Group into rows where floor items share similar depth (spread < 10cm)
3. Fill each row across the trailer width before advancing
4. Stack small items on floor-item footprints, preferring same-category slots
5. Insert 5cm load-bar gaps every 3m along the trailer length

Tech stack

Known limitations

• Rounded corners. LiDAR struggles with smooth curves at distance, so the app prompts you to move closer when confidence drops.
• Suspended edges. Objects in open air may cause raycasts to land on the background. Measure top-down for the best result.
• Distance. Accuracy degrades past 3m (around 5–10cm error). Auto-scale helps, but LiDAR sensor resolution is the bottleneck.
• Network for export. Push to Truck Packer requires a network connection. CSV, Excel, and PDF exports work fully offline.
• AR drift. 1–2cm of drift is inherent to ARKit world tracking. Move the device slowly for the best accuracy.

Privacy

All scanning is performed locally on the device using ARKit. Depth maps and camera frames never leave your phone. The only permission the app requests is the camera, for AR measurement. Sign-in uses Clerk for authentication; sync uses the same Convex backend as the Truck Packer web app, with the same data residency and security guarantees.

Get access

Cargo Measure AR is in open TestFlight beta. Sign in with your Truck Packer account on the Cargo Measure AR page to grab the TestFlight link, install the build, and start scanning. Questions? Email help@backlinelogic.com.