http://bbs.aiyingli.com/forum.php
http://www.eoeandroid.com/
http://www.javaapk.com/demo
http://www.androidbegin.com/
http://www.apkbus.com/
http://code.taobao.org/project/explore/
https://github.com/
https://f-droid.org/repository/browse/
http://www.java2s.com/Open-Source/Android_Free_Code/index.htm
https://github.com/aosp-exchange-group/share
To be continue -------