Mars Explorer is an Android application. The app retrieves images sent from the three exploration rovers currently on Mars - Curiosity, Opportunity, and (now defunct) Spirit and displays them neatly for the user to browse.
You can chose to be part of the test group by clicking on this opt-in link.
As an alternative, all the released APKs can be found in the Download directory.
Any kind of contribution will be appreciated; feel free to create a pull request or file issues on the issue tracker. If you'd like to contact me, you can reach me at kartikeykushwaha.apps[at]gmail.com.