Thank you for your suggestion.
Of course, I can use this site to create a polyline, but my problem is to do that “on the lines of the PNG”…
Unfortunately, I cannot add an image to the map to “draw on the image”.
If you don’t have used the stand alone JOSM editor before, there is a learning curve.
The first step is learning how to use the editor to do “normal” changes.
Then when you understand how to enter roads, buildings to OSM, you can try the PicLayer.
I don’t know if the more popular web editor (ID) has any functions to do what you want.
OK, I’ll try it…
Currently I downloaded the JAR file (I’m using Linux) and I can start it.
Unfortunately, if I try to download the “region” for Germany, I get the error, that this is too big. Any idea how to “increase the max data”?
Drawing lines and areas are done with “Draw node” tool (short key A). You click and draw node (points for the line). Then you have to set tags on the line. Depending what the line represent. There are lot of options here. All this is basic knowledge you have to know, when you are using JOSM.
Have you tried using a georeferencing tool to extract the coordinates of the regions in your PNG map? This can help you draw the regions in your app. If you’re new to this, perhaps you can explore some popular programs for georeferencing images and selecting lines to get the coordinates.