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Me before I learned how to use JOSM
(lemmy.ca)
Overview:
Discussion on the Openstreetmap service that has the most open map data that began in 2004.
Apps:
JOSM: Map editor
Organic Maps: Offline maps that's great for walking/hiking/cycling
Magic Earth: Great for driving
Related:
Me when I notice that Helsinki's public transport app uses OSM and you can just search for connections to a place of interest as if you were using CoMaps.