I am the Data Capture and Utilization Technical Advisor at FHI 360. I have used ODK since 2012, when I flew out to Dollo Ado refugee camps in Ethiopia with two suitcases full of Samsung Galaxy Tab 2s and a satellite internet uplink to pilot 'digital' household surveys for the UNHCR Innovation Initiative. Over a decade later I have trained hundreds of users to collect data with ODK and design their own tools in Afghanistan, Ethiopia, Haiti, Ghana, Liberia, Nigeria, Rwanda, Tanzania, Tunisia and many other locations I can't recall right now.

My favorite feature of ODK is the ability to use combinations of relevant rules, calculations, notes, and text piping to create instant within-form reports with data analysis and text-based feedback for users without reliable internet.