MapQuest recently released its own free voice navigation app for the iPhone and BlackBerry.

From the website: “The MapQuest 4 Mobile downloadable application provides easy access to Directions, Maps, and Local Search. With MapQuest 4 Mobile you also have the ability to integrate your saved maps and directions on to the MapQuest 4 Mobile mobile application. To start saving your maps and directions generated at”

Mapquest 4 Mobile

Mapquest 4 Mobile

Via Lifehacker: MapQuest 4 Mobile features voice guidance, off-route assistance (it can automatically re-route you), point-of-interest integration, and plain-text search. (being able to simply search for a location by name is great.) The maps and directions are all downloaded as you go from MapQuest, so it’s also a very lightweight download (“offline” GPS apps are often several gigabytes); the downside to that is that it won’t work if you don’t have a data connection.

MapQuest 4 Mobile isn’t as polished as Google Maps Navigation. It doesn’t rotate the map based on the direction you’re heading, no Street View, no search by voice, no traffic information. mapquest

MapQuest 4 Mobile is a free download.

It’ll be interesting to see whether this competes at all (either in its current form or what it morphs into) with vehicle tracking systems in the future.