in addition to the operating system and some open-source components, the default Android installation program includes some proprietary Google applications, like Gmail, YouTube, and GoogleMap, these are not open-source, the same does not include the android open Code library. As long as the customized ROMs does not include closed-source applications, Google welcomes developers to 'custom android '.
this open Android alliance, currently, the Google Code platform is planned to release its source code under GNU General Public License Version 3 (gplv3). That is to say, all the code of this project will remain open-source forever. But it is still unclear that Google will support the name of the initiative or use the Trademark Law to crack it.