MapSwipe: find buildings and roads in satellite images for humanitarian maps
MapSwipe volunteers go through satellite images and mark the cells that contain requested features (buildings, roads, waterways), compare before and after images of events, and check whether existing map data is complete and accurate. You can take part in a browser at web.mapswipe.org or in the mobile app for Android and iOS. MapSwipe is part of the Missing Maps project, and the results help organisations such as Médecins Sans Frontières. The page states no age limit, language requirement or deadline.
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