“Navfree USA for iPhone offers turn-by-turn navigation, voice guidance, integrated Google search, and map updates for life–all for free. ” -cNet
Read more: http://reviews.cnet.com/8301-19512_7-20026472-233.html#ixzz1Ba9NUaq2

The Navfree app for iPhone is a totally free turn by turn navigation application that uses the OpenStreetMap database as the foundation for its maps and road data. It offers integrated Google searching for points of interest and addresses. Best of all, everything but the Google integration resides on the phone so using it doesn’t incur data charges.

Pros:

  • The map is dead on. My 5 year old Tom Tom has had three map updates since I got it. Interestingly enough the maps for my local area aren’t as accurate after three updates as they were originally.  The maps in Navfree are current with the exception of an intersection that changed when a road was rerouted due to a construction project about six months ago, so I logged into my OSM account and corrected it. Also several changes I made to the OSM data months ago are represented as well while Google maps and even county data remains incorrect.
  • Unlike on the Tom Tom, the map goes from daylight colors to night colors automatically and it’s pretty close to the actual setting of the sun give or take 15 minutes.
  • The map zooms out when you are going fast so you can see more of the road ahead, you slow down the map zooms in.
  • It does in fact use no data while traveling. This is a bonus for some one with a limited data package.
  • Recalcs are fast. Faster than on the Tom Tom and GPS satellite acquisition is faster than the Tom Tom.
  • If you are playing music on the iPhone while the app is running the music will fade in and out as the directions are spoken.
  • The interface has a utility for reporting issues with the map data, so the end user can help to fix inaccurate areas.

Cons:

  • Many addresses are not in the database, forcing you to place a marker on the map for your destination. This should get better over time once they start geocoding the address ranges.
  • The menu’s are not easy enough to use while driving down the road. The menu structure is also not as intuitive as on standalone GPS devices, making it difficult to use on the road.
  • Setting a destination is difficult and somewhat clunky compared to competing products. May be a result of the address database, but navigating to a cross street is difficult as well.
  • Route planning: The roads database is not configured correctly and sometimes the application confuses fastest with shortest route, taking you down two lane roads in a city rather than staying to 4 lane roads with fewer lights and stops. In one instance the app routed me through the center of a town instead of taking me along a bypass directly to my destination. After checking the OSM data it’s clear that some major roads have been designated as secondary, so that the application cannot distinguish between a residential cross street and a main thoroughfare. Changing this in the OSM data is easy, but it’s unclear how frequently these updates will be applied to the maps on the phone.
  • In town Turn by Turn voice instructions became annoying however since it reminds you more often than the Tom Tom. Also the short directions, like “Turn Left” faded in too slowly so all you hear is “Left” or nothing at all. But by the time it’s using the short one you’ve heard it twice already.
  • Map accuracy can be an issue since the application relies on crowd sourced data, so if an area hasn’t been given any attention by one the contributors you’ll end up with nothing at all for that section of the map. During a quick review of the I-20 corridor between Columbia and  Florence I noticed a few subdivisions that weren’t mapped.
  • Charging – This program really drains the battery fast. It’s recommended you have the phone on a car charger while this app is running. In fact, if your phone has less than a full charge it will not charge at all while the app is running, but remain at the same level.

In summary, this is still a great iPhone application because it’s free, data is stored locally, and it will work as a very coarse navigation system. It will get you into the area you want to go, and for long distances that’s a great utility. It’s still lacking as a door to door solution however, but it bears watching closely and it still a good thing to have in a pinch if you find that your GPS unit is in the other car.