App Inventor for Android from Google Labs

You can build just about any application you can imagine with App Inventor. Often people begin by building games like WhackAMole or games that let you draw funny pictures on your friend's faces. Make use of the phone's sensors to move a ball through a maze based on tilting the phone...

Source: http://appinventor.googlelabs.com/about/

Related article: An Introduction to Android

Its from Google and a Do It Yourself application tool! So, start working today for your own first Android Application Inventor software project!!!