@zverik

For small groups and areas a uMap map might work for notes and lines? Not very mobile friendly though, it's more for display than collection.

For non-OSM data collection in the field I've only heard of QField and Mergin maps. They both rely on a #QGIS file to set up the forms and data layers and I think they can be configured for users to attach photos. I've never used either seriously though (just a hobbyist), so I'm relying on their own case studies/media relations.