Having the ability to work on your GIS projects offline, when network access is unavailable or patchy, is hugely beneficial. The world’s most popular geospatial software, ArcGIS, does have a disconnected offline option where you can continue to edit features. ArcGIS is not free, and thus is not an option for many. So, what free, open-source mapping software is available for use offline? Here, we will go through a collection of the most commonly known free mapping software, and some of the lesser-known options.
QGIS
- Widely popular with a large support community
- Extensive range of plugins to expand included analysis tools
- Compatible with various file types
After ArcGIS, QGIS is the next most well-known and widely used GIS software. It is broadly interoperable with different file and data types, and there are a large number of plugins available to extend its abilities. QGIS offers users much of the same functionality and user interface as ArcGIS, but it is a completely free and open-source software. It offers some advantages, including a smaller installation size and lower computing power requirements. As a result of its popularity, there is a large community of support around QGIS, so tutorials, updates, and bug fixes are readily available.
QGIS has an offline editing plugin, or you can use another program called Mergin Maps, which allows you to package your QGIS projects and use them offline on a mobile device.
To learn more about Mergin Maps from the source, listen to our podcast with the creator here.
Overall, QGIS has some limitations in terms of raster and graphics processing, including 3D imagery, LiDAR, and remote sensing. When used in combination with other processing tools such as GRASS GIS or SAGA GIS, however, QGIS is a standout in the field. No other open-source software offers as much flexibility, power, and variety of features in a single program.
GRASS GIS
- Powerful data processing and analysis tools
- Best used in conjunction with a user-friendly cartographic software
- A long-established project with extensive support and tutorials available
GRASS GIS is not a start-up, and certainly not new to the field. Having been in continuous development since 1982, and originally developed by the US Army Corps of Engineers’ Construction Engineering Research Laboratory (USA/CERL), it was purpose-built for environmental planning and land management. It is now well-known and popular amongst environmental professionals.
GRASS GIS is loaded with tools for data processing and analysis, including 3D, raster, and satellite imagery tools. Because it is so focused on analysis tools, basic cartographic output is limited. GRASS GIS is therefore more commonly used in combination with another design program, such as the Adobe suite or QGIS, for map production.
As GRASS GIS has been around for a long time, there is an extensive network of support and tutorials available. This is particularly useful given that the software has a steeper learning curve initially. GRASS GIS runs on Windows, Linux, and macOS.
SAGA GIS
- Impressive terrain analysis tools
- Includes geostatistical tools for further spatial analysis possibilities
- Easy to use and learn
SAGA GIS, which stands for System for Automated Geoscientific Analyses, was specifically built for geospatial analysis with a particular focus on terrain. Similar to GRASS GIS, it is not optimised for basic cartographic tasks, but it features powerful raster processing and unique analysis toolsets that other programs do not have. As a result of the program’s focus on terrain analysis capabilities, SAGA GIS offers outstanding 3D visualisation. Quality 3D mapping is rare in open-source GIS software, and is more often a paid extension.
As a completely free, open-source software, the breadth of tools available in SAGA GIS is impressive. The program also features a range of geostatistical tools for spatial interpolation. Alongside its high-end analysis capabilities, it is also considered very user-friendly and accessible to newcomers.
SAGA GIS runs on Windows, Linux, and macOS, and requires very little disk space. You can even save the executable files onto a USB drive and share the program amongst colleagues or classmates.
Whitebox Geospatial Analysis Tools
- Great for hydrological analysis
- Can be connected to QGIS as an extension
- Not all analysis tools are available free
Whitebox Geospatial Analysis Tools (GAT), and its successor WhiteboxTools, is a mostly free open-source GIS platform. The free open-core version provides a wide range of powerful geospatial analysis tools; for additional capabilities, there are various paid extensions available. As with many of these open-source software programs, they were originally designed with a specific purpose in mind. Whitebox GAT is especially well suited to hydrological and terrain analysis, as well as LiDAR and image processing. The team has developed a unique range of analysis tools and continues to expand them, even upon request in some instances.
It was developed to be installed quickly and to take up minimal disk space. As a result, the program will run smoothly as soon as you download it, with minimal setup. It can be added to QGIS and ArcGIS as an extension, which is recommended so you can combine the impressive analysis tools of Whitebox with the cartographic functionality of QGIS or ArcGIS.
Want to know more? Listen to John Lindsay talk about how he developed Whitebox Tools and the functionality of this software.
gvSIG
- Android mobile application available
- Excellent 3D rendering ability
- Offers some innovative geospatial tools
gvSIG is not as well-known, yet provides a powerful open-source GIS software that is compatible with various file types. Its true crowning glory is the Android application, which enables you to move smoothly from field data collection to mapping and data analysis. You will even have access to the information stored in these features while in the field.
Boasting over 350 tools in the toolbox, there is everything from geostatistical tools to terrain analysis and remote sensing tools. The gvSIG team is also branching into more innovative areas, including a geosocial toolbox aimed at utilising the spatial data available in social media platforms.
While the maps you can create with gvSIG may not be as visually polished as those from other platforms, it is still fully functional. It has a smaller community of support, but documentation and troubleshooting help are available. gvSIG is a particularly good choice where field data collection is a priority and a capable desktop GIS is required alongside it.
OpenJUMP GIS
- Good for simple vector editing
- Can handle GML files
- Infrequent software updates
OpenJUMP, a community fork of JUMP (Java Unified Mapping Platform), was initially developed for vector data editing and viewing. It works with different file types, including ESRI shapefiles and Geography Markup Language (GML), which may be helpful for some workflows.
This software provides a limited range of GIS mapping abilities, and while it can handle raster projections, you will not be able to do much else other than view them. If all you need to do is edit geometry-based features and attribute data, then this will work fine for you. The software is still supported, however updates are infrequent and there is only a small community around it.
uDig GIS
- Easy to use GIS software
- Basic, yet capable of complex vector data processing
- Good all-round use
The uDig acronym (User-friendly Desktop Internet GIS) best describes the software as a whole. uDig is user-friendly, compatible across a range of desktop platforms (Windows, Linux, or macOS), web mapping ready, and provides a solid collection of geospatial analytical functions. uDig was primarily developed for database editing and viewing, especially for biodiversity and forestry management.
There is the ability to import quality base maps and web map tiles, and once you enable the spatial toolbox, you will have the ability to complete even complex vector data processing. uDig does not have a large community for support, nor does it receive frequent updates. The concept and framework of this software is sound, but it has not progressed or expanded enough to be competitive.
CloudCompare
- Powerful 3D point cloud processing
- Can efficiently handle large files
- Cross-platform functionality
For something more specialised, there is CloudCompare. CloudCompare was designed for editing and processing 3D point cloud data, commonly acquired from LiDAR or photogrammetry workflows. As a free software, this kind of 3D processing is quite impressive. The program includes a wide range of point cloud processing and display tools. The software was developed to import and rescale data, so you can process and store these very large files without losing precision (depending on your computer and graphics card). CloudCompare runs on Windows, Linux, and macOS.
MapWindow
- Specialised software for hydrology
- Small community of users
- Not well supported within the broader GIS community
MapWindow was primarily developed for watershed modelling and analysis, and has been adopted by the US Environmental Protection Agency as the GIS platform underpinning its BASINS (Better Assessment Science Integrating Point and Nonpoint Sources) watershed analysis software. It can perform most of the GIS functions you would need, and is highly specialised in hydrology-related functions. Outside of watershed applications, MapWindow will likely not be the best fit for more general GIS workflows.
OSGeoLive
OSGeoLive is a little different to the rest in that it is a self-contained bootable environment that can be saved onto a USB drive or DVD, or run through a virtual machine. It provides access to over 50 pre-installed open-source geospatial applications, many of which are mentioned in this article. Essentially, you can get them all in one place with OSGeoLive.
The benefits of this are widely seen in training and workshops. It avoids the hassle of troubleshooting the installation process, and allows you to start working immediately. All the startup information and tutorials are included, and a range of vector and raster base maps and other data sources are pre-loaded. There is also a plugin available for QGIS. One of the best features is that an OSGeoLive environment can be launched and used completely offline.
Want to learn more? Listen here to find out more from our podcast about OSGeoLive.
Open-source GIS Software Will Not Hold You Back
Not being able to afford a GIS software licence need not hold you back. The range of free, open-source software available today is simply staggering. While QGIS is by far the most well-known open-source option, there are a number of smaller tools that offer impressive processing and analytics capabilities — particularly if you are working in a specialist field that has developed its own open-source program.
