Note that if some data is missing or wrong - you can fix it by editing on https://www.openstreetmap.org/ as they use OpenStreetMap data

Such help is really welcome!

If you are on Android then I recommend StreetComplete which asks questions and edits OSM based on answers (disclaimer: I wrote parts of it)

(Organic Maps has some limited editing capability, but for example you will not change road geometry or add forest area with it)