Open viewers. Designed for exploration.

From enterprise GIS platforms and geoportals to web experiences using open-source components. Six real references to imagine the result and choose how to build it.

See the migration path ↓

Terraes

Property and territory · Latin America

A map designed around a clear task.

MapLibre GL JS / React / TypeScript

Terraes lets people search for an address, explore an area and inspect available price references. The map is the main workspace, with controls and contextual information around the search.

The design decision: A dark basemap gives data colors room to stand out. Visible search, a persistent legend and a contextual panel focus attention on the selected area.
How to apply it to your platform: Use this pattern for parcel lookup, property observatories and citizen portals: find a place, understand its data and take a specific next step.

An application using open components: its viewer uses MapLibre. It is not presented as a fully open-source application or evidence of replacing a proprietary platform. Data and price-reference availability vary by location.

Terraes ↗

Three ways to make data visible.

We selected these experiences for their visual hierarchy, use of color and connection between map and task. They are third-party editorial references, not GeoSAT projects or evidence of replacing ArcGIS.

02 / kepler.gldeck.gl · MapLibre · React

Official kepler.gl visualization with colored hexagonal columns over a dark map. — © kepler.gl contributors · MITImage source Terms

Visual analytics · Mobility and operations

Give density a shape.

Hexagons, arcs and time filters turn geographic datasets into patterns people can explore.

The design decision: Height and color reveal concentrations. Filters connect the visualization to an analytical question.
How to apply it to your platform: A reference for trips, commercial coverage and asset distribution. Define aggregation and the legend before choosing 3D.

MIT software. Basemaps, providers and data have separate terms; the viewer license does not automatically cover them.

kepler.gl · GitHub ↗

03 / Digital Earth AustraliaTerriaJS · CesiumJS · OGC

Official DEA Maps example with a comparison divider between satellite images. — © Commonwealth of Australia (Geoscience Australia) 2026 · CC BY 4.0Image source Terms

Earth observation · Comparison

Make change visible.

Geoscience Australia combines a catalog, imagery and comparison in a TerriaJS-based experience.

The design decision: A divider compares imagery in the same view. The catalog retains context and provenance.
How to apply it to your platform: A reference for land-cover comparison, construction progress or environmental change, with dates and resolution under control.

TerriaJS is Apache 2.0 software. The portal and its datasets retain their specific terms and attribution requirements.

DEA Maps · About ↗

04 / NASA WorldviewOpenLayers · GIBS · WMTS

Official NASA Worldview image with satellite layers over Brisbane and a timeline. — NASA Worldview · NASA / ESDISImage source Terms

Satellite imagery · Time

Navigate through time, too.

Worldview uses OpenLayers to explore NASA GIBS imagery. The date is part of navigating the map.

The design decision: The timeline remains beside the layers so users can understand which image they are viewing and when it was acquired.
How to apply it to your platform: A reference for fire, flood or land-cover monitoring; imagery needs both context and a date.

Code published under NASA Open Source Agreement 1.3. Check data terms for each product. NASA does not endorse GeoSAT services.

NASA Worldview · GitHub ↗

Ocean activity · Temporal data

Global Fishing Watch

From global activity to a specific track.

A useful reference for combining a map, activity and time in an investigation.

The design decision: Restrained color, thematic layers and a shared time scale help users move from density to detail.
How to apply it to your platform: Inform fleet and operational activity interfaces, subject to data permissions and quality.

Publishes open technology and components. Public map access is not commercial permission for its data or images; review each service’s terms.

Global Fishing Watch · Technology ↗

Explore the reference ↗

Weather · Scientific visualization

earth.nullschool.net

Motion that explains a phenomenon.

Wind visualization turns direction and magnitude into a memorable cartographic experience.

The design decision: Particles communicate motion; the color scale expresses another variable. Animation has a purpose.
How to apply it to your platform: A visual reference for wind and currents. An institutional product also needs pause, reduced motion and a static reading.

Its about page links to a free version of the code. This does not mean that version reproduces the full current site or that commercial assets are freely reusable.

earth · About ↗

Explore the reference ↗

Reference images, not live data. Each project retains its attribution. Linked sites may change; software, data and service terms are evaluated separately. Selection reviewed September 23, 2026.

WebGIS → Open GIS

Change the viewer. Keep the knowledge.

A new interface must preserve the tasks that matter. Start by identifying what your platform does today, who uses it and which modules need continuity.

ArcGIS, VertiGIS, CARTO, SuperMap and other platforms address different needs. We review versions, contracts and integrations before proposing what to retain, upgrade, decouple or migrate. The pilot must demonstrate workflow continuity regardless of the original vendor.

Geoportals and modernization: scope and assessment →

What to preserve when migrating a viewer
Workflow	What to inventory	How to verify it
Search and lookup	Address, identifier, record and attachments	Find the same records and distinguish missing data from errors.
Layers and styling	Catalog, scales, legends and labels	Compare reference views; check CRS, layer order and dates.
Permissions	Roles, authentication and organization filters	Test allowed and denied API access, beyond hiding interface buttons.
Editing and processes	Forms, validations and states	Reproduce rules, concurrency, history and attachments with process users.
Reports and exports	PDF, CSV, GeoJSON and consumed services	Compare fields, totals, geometries and integration contracts.
Operations	Monitoring, backups, deployment and support	Rehearse restoration, source failures and rollback.

Read the full migration guide →Try GeoSAT viewers →

An open path from different platforms.

Compare the system you have with the tasks you need. These families serve different purposes; the guide identifies dependencies and what to validate before migrating.

Enterprise GIS and geoportals

Esri ArcGIS · VertiGIS / Geocortex · Hexagon M.App Enterprise · Octave GeoMedia / Alto (Luciad) · Precisely MapInfo / Spectrum Spatial · SuperMap · H&G MapGIS

Compare services, identity, catalogs, applications and configured workflows.

Spatial analytics and fieldwork

CARTO · GIS Cloud

Evaluate queries, processing, forms and synchronization separately.

Engineering, infrastructure and networks

Bentley OpenCities Map · Autodesk AutoCAD Map 3D · GE Vernova Smallworld

A lookup viewer does not replace design rules or a network model.

Maps and location APIs

Mapbox · Google Maps Platform · HERE · TomTom · MapTiler

Separate the renderer from basemaps, search, routes, data and usage terms.

Compare platforms, alternatives and costs →

Choose technology for the work it needs to do.

A viewer is one layer of the solution. PostGIS organizes data; GeoServer, QGIS Server or pygeoapi can publish it. The map engine, identity and business rules complete the experience.

MapLibre GL JSA viewer with its own identity

Search, vector tiles and contextual records.

Work still required: Build forms, identity, permissions and operations.

Project documentation ↗

OpenLayersGeoportals and interoperability

Raster/vector layers, projections and OGC services.

Work still required: Design the catalog, mobile experience and access controls.

Project documentation ↗

TerriaJS / CesiumJSCatalogs and 3D scenarios

Terrain, federated catalogs and layer comparison.

Work still required: Prepare 3D Tiles and review providers, formats and costs.

Project documentation ↗

deck.gl / kepler.glAnalytical exploration

Aggregations, tracks and temporal filters.

Work still required: Design data publication and the business workflow.

Project documentation ↗

QGIS Server / LizmapPublish QGIS projects

Desktop-authored cartography and web lookup.

Work still required: Check plugins, editing, versions and security configuration.

Project documentation ↗

Your own design. Costs you can explain.

Open software can reduce certain license costs and give you more control over the interface. Total cost also includes development, infrastructure, map providers, security, training and support.

Calculate transition and operations using my figures →

FIRST PILOT SCOPE

One complete task: find, inspect and export.
Representative data and agreed user profiles.
A desktop and mobile viewer, with an alternative to the map.
Access, integrity, performance and recovery checks.
Documented architecture, code and operating cost.

Assess my viewer migration →

Before choosing an open geospatial viewer

Can an enterprise GIS platform be modernized with an open-source viewer?

Components and workflows can be replaced where access, export and usage rights permit. First inventory the version, modules, data and integrations. MapLibre or OpenLayers cover the viewer; full platform equivalence requires APIs, business rules, permissions and operations.

What does the Terraes example demonstrate?

Terraes shows how to integrate MapLibre into a territorial lookup product. The reference demonstrates a design and technology choice; it does not attribute a vendor replacement, measured savings or an open-source license to the entire application.

Can ArcGIS stay during the transition?

Yes, where each service’s version, access and terms permit. A new viewer can coexist with current services while other layers are tested for replacement. Retained licenses remain part of total cost.

How much does an open geospatial viewer save?

There is no universal percentage. Compare construction and transition, licenses that can actually be retired, cloud, basemaps, data, geocoding, support, security and training. Net savings can be positive, zero or negative.

Which open-source geospatial viewer is best?

It depends on the work: MapLibre for custom vector interfaces, OpenLayers for geoportals and interoperability, TerriaJS and CesiumJS for catalogs and 3D, kepler.gl for analytical exploration and Lizmap for publishing QGIS projects. Validate the choice with your data and users.

Mentioned trademarks belong to their owners; inclusion does not imply affiliation with or endorsement by those vendors. Terraes is identified as a product example from the GeoSAT ecosystem. The other references are external projects.