AndroidのWiki
http://www.google.co.jp/url?sa=t&rct=j&q=android&source=web&cd=1&ved=0CD8QFjAA&url=http%3A%2F%2Fja.wikipedia.org%2Fwiki%2FAndroid&ei=CTkaT6fbM8a1iQef96HYCw&usg=AFQjCNEsV1W5k4_plGMrSp4jhYrOfqvAjg&sig2=I3bPCs2cwO2RY8_ZWdctOg&cad=rja

Android開発者向けページ
http://developer.android.com/index.html