The Best

I have ALL significant navigation apps on my iPhone. There are some really good ones available. IGO been the most recent of my downloads but is easily my favorite!
The good:
- it is not well advertised in the app description, but they have an awesome speed display and warning. Other apps advertise it then only cover major roads.
- Lots of bad reviews on the download of maps to your phone, but ALL apps go thru this process if they store maps on the phone. You DO need high speed internet though for efficiency. IGO downloads as well as any other onboard map app.
- Clear and precise verbal instructions.
- Colorful, precise, easily readable, and accurate map displays.
- Current and ubiquitous POI database.
- Easy setup of multi destination routes.
NOT SO GOOD:
- A minor annoyance is the tendency to restart the route to a destination after driving past it. That usually does not happen though if you stop when it recognizes end of destination.

Djr805 about North America - iGO primo app, v2.7.0