What phone are you considering as this makes a big difference to the choices available?
Apples iFone has a decent array of Nav applications, The Windows Mobile Pocket PC based devices made by HTC are also worth considering but the applications available are becomming rather old/ limited then there is the Nokia system which I have never bothered with so cannot comment on whats out there!
For iFone:
Navigon
TomTom
Sygic
I-Go
Co-Pilot
+ quite a few others
For PPC
TomTom (device dependent)
Co-Pilot
I-Go
Sygic
There are others but not established brands (I have proably forgotten a few as well)
The choice really comes down to what you want from the application and what phone you want to run it on, I hate to say this but the iFone has the best selection of options for navigation using current maps (which is more important than anything else) and being a connected device (internet) it offers greater capability when in the car - I really need to go and chill out having said the iFone beats the other platforms as I honestly never though I would ever come out with such a statement! But at the moment its true, probably due to the software creators spending more time on iFone apps than PPC due to volume sales, but why buy in to a platform (PPC hardware) that isn't looking to clever for software choice etc.
Only today I did 400 miles and only took the iPhone in the car, I have various applications available for navigation/ speed camera warning etc and at times its difficult to decide which is best to use, Navigon is very good (bear in mind I am UK based) TomTom is also very good, Sygic is by far the best for running a custom Speed camera database on (if the iFone is jail broken).
One other thing I will add about the iFone is the built in GPS receiver is crap, probably on a par with receivers that were around 5+ years ago in terms of sensitivity, I do use a TomTom car kit to house the iFone which offers greater GPS reception on a par with modern PND type devices, this adds further cost to the solution but is worth considering, I think Navigon also have GPS equipped mount for the iFone about to be shipped which might be worth considering (if you want to switch to an iFone)
The above might give you a few ideas, but post back with the hardware you are considering and factor in a decent powered car holder for the device to secure the rather costly phone and power it as Nav apps seriously clobber the battery - At the end of the day it all depends what you (as an individual) expects from the phone and the nav app - Mike
Thread moved to more appropriate forum section - Mike
