It was mentioned in the weeklyOSM as having been used for strengthening disaster risk reduction efforts: https://weeklyosm.eu/archives/18130

The steps:

  1. Define an area of interest
  2. Run a map quality check
  3. Export a PDF of the sketch map and let locals fill it out with relevant markings
  4. Scan / photograph the marked up sketch map
  5. Upload to sketch maps to get the collected markings as geodata

Some FAQs:

So far the Sketch Map Tool has only been tested on neighborhood or city level. The tool works best for study areas which are smaller than 50km².

Please make sure not to accidentally mark the globes at the edge as they are needed for automatic map detection. Use thicker felt-tip pens with intense colors; red, blue, and black work best. Prepare the same set of pens for all interviewers.