Waze is a crowd-sourced GPS navigation app, now with voice actions. This is an app like TOM TOM but free. I would not expect the same quality but it will do the job.

What makes Waze unique is that in this update, the app includes voice commands like “take me home” that you can activate by waving your hand in front of the iPhone’s screen.

The app cleverly uses the iPhone’s proximity sensor to detect your waving hand and activate voice commands.

Free Navigation App for iPhone [GPS]