1. Navmii Italy
I can't speak highly enough about this app, not just the price, it is also a great app. Lets talk about the price first, as I investigated tom tom and other alternatives and found them to be 10 or 20 times as expensive and forcing me to buy maps for all of europe in some cases.
We weent to southern Tuscany, a bit out in the wilds but wanted to visit a few of the sights whilst we were there. So flew in to pisa and it got me out of Pisa and on the Autopstrada in no time, but what was good about it was it found the place we were staying that was in the middle of nowhere. Then we used it on all our excursions from Saturnia to Siena and some wild and wonderful places in between. It didn't flalter or fail, although sometimes the signal to the iphone was not that great.
The thing with these kind of apps is you try them and then build a trust in them, in our case this trust was built quickly and I would be happy to recommend it to anyone
2. If you are going to buy the above app for your iphone and use it as a sat nav system then you need a holder, to fit on the windscreen or dashboard. we bought the one below because it was low cost and good quality, easy to fit and it came with its own charger. We only have the Iphone 3GS, but a friend recommended the second one for the iPhone 4.
"Car Charger Windscreen Holder Mount For Apple iPhone 3G 3Gs" (greymobiles)
This is the one for the iPhone 4
The navmii system combined with an iphone was an absolute must for getting around southern tuscany and with our limited Italian, we valued this and really something you should pack along with your tooth brush.
