I finally started to fill data in to #OpenStreetMap.
At first I just looked at how several features are already tagged, then slowly started to correct wrong data and then add missing details.
I use #StreetComplete app to add details on walk travels,
#OsmAnd app to add POIs and of course the iD web editor for larger edits.
I am especially impressed by the iD editor. It's so helpfull with clever use of autocomplete and linking to #OSM wiki...
The best reward is 3D view becoming more realistic...
@stepan to add details on-the-go you can also try @everydoor