QGIS

QGIS is a desktop geographic information system that runs on Windows, macOS and Linux. It is an OSGeo project released under the GNU GPLv2+ licence. Gary Sherman started it in 2002 as Quantum GIS. The QGIS Development Team and volunteer contributors now maintain it, and the 4.x series moved it onto the Qt6 framework. QGIS handles vector, raster, mesh and point cloud layers. Its tools cover cartography, print layouts and atlases, digitizing, custom attribute forms, a large set of processing algorithms, and a graphical model builder for automating workflows. Point clouds load from LAS, LAZ, EPT and virtual point cloud files, and you can render them by classification and filter them with PDAL expressions. QGIS cannot edit point clouds itself; for that it points users to CloudCompare or PDAL. You can extend it with Python or C++ plugins, and it connects to PostGIS, SpatiaLite, MySQL and standard web map services. The software has no licence fees. Organisations that need help usually pay third-party support providers or certified trainers, and many fund the project through sustaining memberships. For field data collection, the separate QField app syncs QGIS projects to phones and tablets. QGIS suits utilities, local government, consultancies and engineering firms that want an alternative to ArcGIS without per-seat costs. It is a GIS, though, not an asset maintenance system. It has no work orders, maintenance scheduling or sensor monitoring out of the box. Reviewers also report slow performance and crashes on large datasets, and a steep learning curve for newcomers.