I don't think you will get any turn-by-turn voice navi for free. If you don't need that, then you can just as well use the google one on the phone, works perfectly.
Paid for apps, ndrive and CoPilot are pretty cool and you get a free trial on them.
The instructions and pronounciations are still a bit iffy, especially for non-english road names, but it gets you from A to B well enough. Did I mention it is FREE