Think of one activity as one field event
One activity can represent a site visit, a finding, a completion step, or another discrete field event. The important part is that the evidence stays grouped as one reviewable record.
What can be inside it
An activity can include notes, one or more media items, timestamps, GPS, and measurement context. That keeps the factual record connected instead of scattering it across separate systems or files.
Why this improves review
Because the evidence stays together, supervisors and managers can consume it from the web without losing the relationship between the note, the media, the time, and the location.
This also makes follow-up actions such as commenting, saving, and sharing more useful, because the action is attached to the complete record rather than to only one part of it.
How to use the model well
Keep one real field event in one activity. Do not overload a single activity with unrelated updates just to reduce counts. Survee works best when each activity is a coherent piece of evidence.