Is OSM up-to-date
Is OSM up-to-date? (is-osm-uptodate.frafra.eu) looks for old and potentially outdated nodes and ways.
The rationale behind this application is that nodes and ways that have not been modified since a long time have an higher probability of containing outdated information: having a map showing features coloured differently based on their last modification time allow the user to easily spot potentially wrong values and positions.
Clicking on a point or on a way opens a pop-up, which displays basic information and useful links to openstreetmap.org functionalities and references to wiki.openstreetmap.org. The refresh button fetches new nodes contained in the portion of the map that the user is looking at. It is also possible to share the current view with other users just copying the link because it contains an hash which represents the last position and zoom level.
The application provides simple REST API and a command line interface which do not require a web server or a web browser; the output is a geoJSON valid file.