About OpenSurvey3D

A free, open-source field app from Laan Labs

Centimeter-capable GNSS hardware has become dramatically more accessible. The field software around it is still too often tied to one receiver, gated behind a recurring subscription, or designed as a desktop GIS form that happens to fit on a phone.

OpenSurvey3D is our survey-first answer: a native SwiftUI app that starts with the location service already in an iPhone or iPad, scales to external NMEA and RTK positioning, captures measured features and georeferenced 3D evidence in one project, and guides the operator back to those assets in AR. There is no account requirement and no subscription between opening the app and taking a shot.

What the app covers now

  • Projects and field collection. Points, lines, areas, routes, photos, video, notes, typed attributes, guided averaging, auto capture, offset shots, and manual map placement.
  • GNSS and corrections. Built-in GPS, Emlid Reach and Bad Elf Flex receivers over Bluetooth, Leica Zeno through Zeno Connect, NMEA over Wi-Fi TCP, NTRIP profiles and mountpoint browsing, ITRF-to-NAD83(2011) shifts, GEOID18 elevations, live solution health, and automatic reconnect.
  • Design and stakeout. Import points, lines, and alignments from CSV, PNEZD, GeoJSON, DXF, LandXML, GeoPackage, Shapefile, GPX, or KML, then stake to a point, a typed northing and easting, or a line by station and offset, with live distance, bearing, offsets, tolerance, cut and fill, and as-staked records.
  • 3D scanning and context. LiDAR point-cloud and photogrammetry workflows anchored to survey observations, plus terrain-and-imagery site models with points, routes, profiles, and scans.
  • AR asset finding. Open one target or a whole project through the camera, follow live direction and distance to nearby stored assets, then switch to numeric stakeout when a position must be set.
  • Quality and handoff. Positioning pedigree, known-point checks, residuals, project RMS, exceptions, PDF/HTML QA reports, closure sheets, and CSV, PNEZD, GeoJSON, DXF, LandXML, GeoPackage and Shapefile in your state plane zone, LAS, ground-scaled, ZIP, and terrain OBJ exports.
  • Sharing. Share online sends a project to a web map link anyone can open in a browser, with no account on either side, and the share server can run on your own machine.

Who's building it

Laan Labs is a small independent studio with more than 70 million app downloads and deep experience in Metal rendering, ARKit, LiDAR capture, photogrammetry, and computer vision. OpenSurvey3D sits beside two other open-source tools from the studio:

  • OpenShape3D — direct-modeling CAD for iPad and iPhone, built on the OpenCASCADE geometry kernel.
  • OpenPlan3D — browser-first floor plans in 2D and 3D, with real exports and an iPhone LiDAR capture companion.

Our principles

  • Survey-first. The receiver–collection–check–deliverable loop is the product.
  • Receiver-agnostic. Support open position streams and corrections without turning the app into an accessory lock.
  • Honest accuracy. Keep the receiver's estimate separate from observed check-shot residuals, and preserve the evidence behind both.
  • Open handoff. Feature codes, geometry, attributes, coordinate frame, and QA belong in files the receiving office can inspect.
  • Your data is yours. Local-first storage, no mandatory account, no proprietary export gate.

Open source and project status

The iPhone and iPad app is free on the App Store and requires iOS 26.2 or later. The native project is available on GitHub under the MIT license, including the GNSS pipeline, projection engine, project database, QA logic, and open-format exporters.

Share online gives a read-only web map of a project, and its share server is on GitHub for anyone who wants to host it. A synced browser workspace for editing projects remains on the roadmap. We call that out plainly because the local iOS workflow and its exports are designed to stand on their own today.