Trace upload open source code

I have written a simple Android OSM browser/navigator app. It is located here:

https://play.google.com/store/apps/details?id=com.gulfislandsystems.routeguide

I would like to add an OSM “trace upload” feature to the app to allow users to upload their GPS traces to OSM. Does anyone know of any open source code that can do this? Or at least an example of how to talk to the OSM servers. Thanks.

Do you already know the API-Description?