I am having a good time with TomTom. I have not used any other one. I don't like it being a 2gb install, but I know why and understand. I hear Navigon is a nice one as well. Thoughts?
+1 for Tom Tom.
MotionX is an off-board navigation application. The maps have to be download over your data connection as you go. If you're not in a 3G area then you will have a hard time with the maps. IT is not really comparable to TomTom or Navigon. It works, and it is probably OK for areas with good 3G, but even the built-in Google maps application sometimes has significant delays in downloading local streets. This is the main reason I went for an application that includes all the maps.
I used TomTom Navigator 6 and Garmin Mobile XT when I had an AT&T Tilt. Now I have Navigon on my iPhone and really like it. They seem to be keeping one step ahead of TomTom in terms of features. The next version even has some 3D terrain representation which is pretty nice. Also, the Navigon traffic subscription is lifetime, with TomTom you pay yearly. Navigon also includes a safety camera database (pretty useful in Europe), there's a yearly fee with TomTom.
I prefer Navigon, but you won't go wrong with either. TomTom is very good too.
It might be helpful to note that MotionX does cache its mapping and turn by turn data. This means that (when you first start it up) it usually downloads the data you will need for the length of the trip. Of course you are also quite right to point out that since MotionX does not have on board maps, it's really quite different from Navigon or Tom Tom. MotionX is only 99 cents (for the first month) but if you go of course (or have to restart the app) in an area without a data connection, it will be unable to re-route you.MotionX is an off-board navigation application. The maps have to be download over your data connection as you go. If you're not in a 3G area then you will have a hard time with the maps. IT is not really comparable to TomTom or Navigon. It works, and it is probably OK for areas with good 3G, but even the built-in Google maps application sometimes has significant delays in downloading local streets. This is the main reason I went for an application that includes all the maps.