We need graphics to publish application in Store (described here https://support.google.com/googleplay/android-developer/support/bin/answer.py?hl=en&answer=1078870)

• Promotional Graphic

• Feature Graphic

Additional informations:

http://android-developers.blogspot.com/2011/10/android-market-featured-image.html

http://xayin.com/thisisatest.html