How many km's from my position to another point on my route

[Louis-trail]

What would help me while walking is: how many km's it is from my current position to another point on my route, which is an imported gpx or kml.
Solutions could be:

1. Calculate distance by putting a dot and calculating the distance over the route.
2. Showing the km's along the route (see attached picture taken from TopoGPS)
3. maybe other

regards, Louis