Essentially, this app is just a white-on-black version of the native black-on-white iPod app, which makes helps you glance at it while driving at night without causing a temporary blind spot in your vision due to the screen brightness.
In addition, as with many of the other listening-while-driving apps we’ve seen, NavMusic ($1) or NavMusic Lite (free) from Soft Objects lets you swipe a finger across the screen in order to adjust volume and skip songs. (The difference between the two versions is that the Lite version has to scan your library each time it opens.)
As such we’re hard-pressed to recommend Nav Music, unless you’re really used to the native iPod app interface, and don’t want to learn something new. In that case, Nav Music fits the bill perfectly, this odd navigation foible aside.
There is one bonus, however — NavMusic supports Apple AirPlay, so if you eventually score a car stereo that works with that wireless protocol, you’ll have another way to play your music over your car stereo (in addition to Bluetooth or a wire).