I'm writing an Android navigation application using Java in my own time as a learning exercise. It reads Shapefiles (with some pre-processing by me) downloaded from http://download.geofabrik.de/europe.html.
I can't find elevation/topographical data in Shapefile format to download anywhere.
Can anyone suggest a free source?
Alternatively, I could invest time in learning another GIS file format and writing code to read it. I'd like to choose a format that can be read quickly by devices with low processing power, and is also likely to be widely used in future.
I want to display elevation data in some form in the navigation application I am writing. I'd like to try various approaches, so data in the form of spot heights or contour lines would be useful.