Once I discovered how well an iPhone can serve as a GPS, I was no longer envious of navigation screen options. I found this program for 99 cents called MotionX GPS Drive, and it does anything I'd looked for in a GPS- maps, navigation, traffic, etc.
But then the search began for a mounting bracket, which has yet to be fulfilled, so here's my current solution :-)
It works just as well with the power cord too, coming up from the lighter.
Yes, it's just velcro tabs!

 

Haha. I do the same thing, but with my EVO!!! It is awesome.

 

I use Google maps for navigation and it was free. It also allows you to make up maps on you home computer or laptop and save them on Googles servers and then just load them to the phone when ready to use them.

Check Craven Speed for mounts that can mount your iPhone off of the Tach. They are a little expensive but are "top quality" units and are adjustable.

http://www.cravenspeed.com/products/...one-Mount.html

 

Thanks, schatzy62.
The mount looks great. It's in the right location. Can you verify that it works with the iPhone 4? The site just says 3 generation.