In the way building cocos2d, box2d… to .a libraries?
You can have a try to build static libs.
Now cocos2d-android can run on android 2.0 or higher. 1.5 & 1.6 is not compatible yet.
As I known, andorid 1.5 only allow to load one .so file.
Does cocos2d-x use any NDK library higher then 1.5, e.g. bitmap?
You can read the changelog on http://developer.android.com/sdk/ndk/index.html OpenGL ES support only ready for 1.6 or higher.
cocos2d is based on OpenGL ES 1.1
Android NDK, Revision 2 (September 2009)
Originally released as “Android 1.6 NDK, Release 1”.
General notes:
* Adds OpenGL ES 1.1 native library support.
* Adds a sample application, san-angeles, that renders 3D graphics through the native OpenGL ES APIs, while managing activity lifecycle with a GLSurfaceView object.
Android NDK, Revision 1 (June 2009)
Originally released as “Android 1.5 NDK, Release 1”.
General notes:
* Includes compiler support (GCC) for ARMv5TE instructions, including Thumb-1 instructions.
* Includes system headers for stable native APIs, documentation, and sample applications.