In which I say nice things about Esri. You have been warned…
A couple of weeks ago, I gave a talk at a local Esri GeoDev Meetup (which also served as a convenient way to tell a room full of developers that my company is hiring developers) on a GeoJSON server object extension for ArcGIS Server that I open-sourced some time ago. I started that effort a little while after giving another talk in which I called on Esri to start supporting GeoJSON. I’m not one to wait around so I built an approach myself.
At the most recent meetup, the Esri staff who were there updated the group on upcoming efforts with regard to GeoJSON. Honestly, I’ve known for some time that there are a lot of people inside Esri who “get it” and that various things have been percolating with regard to GeoJSON.
So I was happy to see the official announcement of support for GeoJSON in ArcGIS Online (AGOL) feature services. Included in the support is access through the REST API using an “f=geojson” parameter. This makes it much easier to consume AGOL services in the web client of your choice. (The announcement shows a Leaflet example.)