The sign information is collected by people like you! The latest version of Scout has a ScoutSigns mobile component built right into the app. If you mount the phone on the windshield while driving with Scout (and you opt in) you will automagically contribute to this fast growing sign database that is free for the OSM community to use. Could not be easier!
- The ScoutSigns User Guide
- ScoutSigns - streamlining road sign data flow to OpenStreetMap on the Scout Developer Platform Blog