I've achieved the loading of OBJ files.... just replace the code in hello world..
/*cube = Primitives.getDoubleCone(20);
cube.calcTextureWrapSpherical();
cube.setTexture("texture");
cube.strip();
cube.build();
world.addObject(cube);*/
by this...
cube = Object3D.mergeAll(Loader.loadOBJ(getResources().getAssets().open("airboat.obj"), null, 10));
cube.build();
world.addObject(cube);
be sure to surround this snippet by a try catch block.
hope this helps.