NASA has built an application “NASA Be A Martian'” for Windows Phone 7, and it is available on the Windows Phone 7 Marketplace.  Here’s information, about their Windows Phone 7 app, directly leveraged from the project they posted on the codeplex site. http://beamartian.codeplex.com/

NASA Be A Martian is an open-source project written in Silverlight for Windows Phone 7. Hosted on Windows Azure and Azure DataMarket, Be A Martian is a community for those who want to become Martian citizens, or are just interested in exploring the Red Planet.

Be A Martian features numerous ways to explore and learn about Mars:
"View" area: here you can check out stunning Mars images, watch videos and animations of future Mars missions.
"Participate" area: this is where we utilize crowdsourcing to allow the public to add to worldwide understanding of Mars by tagging rover images and mapping craters from satellite pictures.
"Learn" area: features here include Mars related news, and a question-and-answer forum that was built using the free Microsoft Townhall framework. More info on Microsoft TownHall can be found at
http://code.msdn.microsoft.com/TownHall.
"Explore" area: a deep-zoom enabled map of the Red Planet with interesting summaries of each different region of Mars.

Be a Martian was created under a Memorandum of Understanding between NASA/JPL-Caltech and Microsoft. The website can be found at beamartian.jpl.nasa.gov.

Screenshots are listed below.

Start Screen View Be A Martian Be A Martian Be A Martian Be A Martian

This application is a great demonstration of the cloud & device integration, and the source-code on codeplex provides a great opportunity for developers to learn Silverlight development for Windows Phone 7.

Check out the application from the Marketplace on your Windows Phone 7 device.