Wow thank you. That is quite feature complete. It is just the ugliest map that I have ever seen. And there seems to be no way of changing the map theme. Will still try it as my default for now. Thanks!
Pocket earth with the contour maps has been my go to offline hiking map for the last 5 years - not many other openstreetmap systems have that countour data.
I think it uses the https://www2.jpl.nasa.gov/srtm/ dataset, which is great, but I did get caught out once by voids in shuttle data meaning there was a 1000m deep hole in the mountain map that wasn’t there!