Project:Musescore API
From London Hackspace Wiki
I wrote an advanced, but currently limited, Java(/Android) API client for Musescore.com. It completely matches the Google Java API client wrappers in structure, such as for Google Books. Best to use with JSON. https://github.com/musescore-com/java-api-wrapper
A Belgian student already created another hack Android app: http://thomasstockx.blogspot.com/