zoom buttons/icons/dropdown/getsures

[routeconverter]

I use RouteConverter on a Win 10 detachable with touch diaplay and would like to easily change the zoom level using touch. Did I simply not recognize such a feature or is it not yet existing?

Dear Georg,

it's simply not existing because I've designed RouteConverter as a desktop application for mouse and keyboard.
So far >99% of the users use mouse and keyboard.

What I looked for respectively ideas how it could be done

You could checkout the source code and try to add support for touch gestures. I'm accepting reasonable Pull Requests if you come up with improvements.