Open Street Maps is great for keeping people up to date and providing assistance to people in need. This may be people that need help getting somewhere. Or people in need of help with emergency cases etc. This is why OEM is so resourceful, they developed their own response team called HOT (The Humanitarian OpenStreetMap) where they ‘The Humanitarian OpenStreetMap Team [HOT] applies the principles of open source and open data sharing for humanitarian response and economic development’ – source: http://hot.openstreetmap.org/. Recently they helped in tracking and containing the outbreak of Ebola in Guinea in early march 2014.
Apple and Foursquare has also started implementing OEM in their platforms as google decided to charge apps and sites using their google maps API. In my opinion this decision was a mistake and it is rapidly backfiring.