Android programming

• Tutorial

http://www.vogella.de/articles/Android/article.html

• How to call web service in web service

http://stackoverflow.com/questions/297586/how-to-call-web-service-with-android

• Managing State in an Android Activity

http://www.eigo.co.uk/Managing-State-in-an-Android-Activity.aspx
Multiple Activities
http://www.mathcs.org/java/android/multi_acts.html