Coming from ArcGIS Online

GratisGIS is a self-hosted portal, a field PWA, and a QGIS plugin for teams that want data custody and want out of ArcGIS Online seat licenses. What is credible today is the portal, sharing, field collection, and QGIS. It is not a full ArcGIS Online replacement, and it is not a drop-in for Experience Builder, Survey123, Field Maps, or enterprise identity depth.

If you are coming from ArcGIS Online, some of the daily work will feel familiar. You create items. Items have an owner and sharing tiers. Maps reference layers. Forms collect features. Web apps can start from a dashboard layout. The names differ, and several Esri products do not have a matching surface here.

What's different:

• Vocabulary. We deliberately don't use Esri's specific words when there's a clearer English equivalent. "Data layer" instead of "feature service." "Map" instead of "web map." "Contributor" instead of "publisher." See Terminology map for the full list.
• Hosting. GratisGIS is self-hosted. You own the hardware, the data, and the license terms. No commercial license fees, no per-credit metering for things like geocoding or routing (you bring your own geocoder or use Nominatim).
• The shape of the data model. Items, sharing, and dependencies work the same way. Underneath, GratisGIS stores everything as a bitemporal observation log; you'll see hints of that in the As of time slider and the per-feature history view, but the day-to-day editor experience is the standard "edit a feature, hit save" loop.

What's here

The pages in this section walk through the most common "how do I do the AGO thing" questions:

• Terminology map. Which AGO term maps to which GratisGIS term. Print this and keep it next to your monitor for week one.
• Feature service to data layer. Moving a layer's content (or just its schema and symbology) over.
• Web map to map. Importing an AGO web map JSON.
• Survey123 to form. Importing an XLSForm.
• App Builder comparison. Where Experience Builder, Web AppBuilder, and Dashboard Designer concepts land here.

What's NOT here

• Wholesale "migrate my org" tooling. There's no one-button import that brings every item from an AGO org into GratisGIS. The format mismatches and sharing-model differences make a fully automated path more dangerous than helpful. The pages here cover the per-item moves; do them deliberately.
• Hybrid mode. GratisGIS can reference an external AGO service as an ArcGIS service item (the data stays on AGO, you proxy through). That's a real ongoing pattern, not a migration step. See ArcGIS service under Items.