I would try Black Star, google it for your mobile GPS, i have the bold and it works well, its not very pretty, and is a little difficult to figure out at first, but it works!! It also has a night vision mode that turns your display red, and is not as bright as the usual bright white background, it allows you to look at your screen after dark, when you look up from your screen you are not blinded, and your eyse adjust quickly!!
Try the link and read about it and there is also a download tab if its is what you want!!!
http://www.blackstarnavigation.com/About.php
Cheers
you might need to copy and paste the link.......