In App Purchase

I want to develop a game on both iphone and Android devices which will have in app purchase and post on facebook feature.
So can we implement these features on both platforms using cocos2d x?

In theory, you can wrap the objc interface to c++ on ios, and invoke java interface via JNI on android
Please reference to the implementation of CocosDenshion on ios & android, it will be the same to IAP & facebook interfaces.