Create shared lib to integrate into JNI under Eclipse

[Opariti]

Hi,
I'm developing for Android NDK under Eclipse in Ubuntu.
Lately I have to create a C++11 .so shared library and call it by a JNI code.
I'm not mastering the Android NDK build process and therefore I'm looking for advice on how to do it properly.
I also have this question: do I have to create the shared library as a "java free" (no MainActivity) project, so that to take advantage of the multi-platform build in one shot (as referenced by the Android.mk and Application.mk files)? I've tried it, it works, but not sure if it is worth the effort (in addition, what library platform should I select?). This solved, the next question would be how to configure the Android.mk file for the calling JNI so that to include the .so module?
I stop here because, although it is a C++ build issue, I don't know if this is the right forum for this topic.
Thanks

[Opariti]

I've found the answer, that may serve someone else:

Yes, it is mandatory to "create the shared library as a java-free (no MainActivity) project". This will generate an output for each platform we specify in the Application.mk file.