For Ubuntu Touch:
Open ubuntu-sdk and use the Ubuntu kit > 15.04

Now open OSMScout/OSMScout.pro
run qmake
build the project
Create Click package and install on device.

When running, the application requires a map to start. 
For now, the map files should go into /media/phablet/<SD_CARD>/Maps/osmscout
The files should be imported on a PC using the Import tool, please refer to the libosmscout documentation for instructions



You can find detailed instruction how to get libraries and applications
build and working in the openstreetmap wiki:

http://wiki.openstreetmap.org/wiki/Libosmscout