Ability to drag & drop various GIS data formats into their interface (they're auto-magically imported into a PostGIS database); robust set of APIs such as the SQL API; Javascript library for integration with web mapping libraries such as Leaflet and Google Maps. Review collected by and hosted on G2.com.
The new Builder interface takes some getting used to, but Carto has plenty of tutorials to help you learn. Review collected by and hosted on G2.com.
