For anyone with an Android device, the Distant Suns(max) app is free today through the Amazon Appstore. This app goes for $5.99 on the Google Play store. I haven’t used this app before, but it’s worth trying out for this price. I'm not sure how long it will be available for free, though.
http://www.amazon.com/exec/obidos/ASIN/B0096YJDNQ
Joe