Full Geo Stack
The stack
Data Store: PostgreSQL
Spatial data store PostGIS, which requires PostgreSQL
Spatial data server GeoServer, which requires Tomcat
Mapnik to generate beautiful base maps
Vector tiles fit in around here somewhere
Map viewer via Leaflet, which requires a web server
Field data collection Open Data Kit, which includes
Android data collection, with web based form designer
and
data upload via Aggregator, which requires Tomcat and Postgres (or MySQL)
The pieces are all open source, but making them work together seamlessly is not free.
What's missing
Make it work seamlessly with ArcGIS. Including working with their new vector tiles. This is probably hopeless.
Make it simple to use a Garmin GPS
What's there but I don't know about it
Topology
Version control
Raster data management
LiDAR data management
Places to get more ideas
fulcrumapp.com
osgeo.org
gdal.org
boundlessgeo.com
amigocloud.com
giscloud.com
opengdp "Open Geo Data Pipeline"
mapbox.com
mapistry.com
mappt.com